JP2006150222A - Cylindrical filter and its production method - Google Patents

Cylindrical filter and its production method Download PDF

Info

Publication number
JP2006150222A
JP2006150222A JP2004344203A JP2004344203A JP2006150222A JP 2006150222 A JP2006150222 A JP 2006150222A JP 2004344203 A JP2004344203 A JP 2004344203A JP 2004344203 A JP2004344203 A JP 2004344203A JP 2006150222 A JP2006150222 A JP 2006150222A
Authority
JP
Japan
Prior art keywords
nonwoven fabric
cylindrical filter
spunbond nonwoven
core
spunbond
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.)
Granted
Application number
JP2004344203A
Other languages
Japanese (ja)
Other versions
JP4751604B2 (en
Inventor
Yosuke Takai
庸輔 高井
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Daiwa Boseki KK
Daiwabo Co Ltd
Daiwabo Polytec Co Ltd
Original Assignee
Daiwa Boseki KK
Daiwabo Co Ltd
Daiwabo Polytec Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Daiwa Boseki KK, Daiwabo Co Ltd, Daiwabo Polytec Co Ltd filed Critical Daiwa Boseki KK
Priority to JP2004344203A priority Critical patent/JP4751604B2/en
Publication of JP2006150222A publication Critical patent/JP2006150222A/en
Application granted granted Critical
Publication of JP4751604B2 publication Critical patent/JP4751604B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cylindrical filter capable of preventing bubbling of a liquid to be filtered and increasing a filtering life, and to provide its production method. <P>SOLUTION: The cylindrical filter (1) has a cylindrical body (10) in which a multi-layer spunbonded fabric (20) consisting a plurality of spunbonded fabrics is wound and adjacent spunbonded fabrics are thermal adhered each other, wherein in the cylindrical body (10), at least one of adjacent spunbonded fabrics consists of a composite resin containing the first thermoplastic resin and the second thermoplastic resin with 10°C higher melting point than the first thermoplastic resin, and in the multi-layer spunbonded fabric (20), a difference of each thermal shrinkage ratio in thermal adhesion temperature of adjacent spunbonded fabrics is 5% or above, and then fineness of strand, by which adjacent spunbonded fabrics are structured each other, is different. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は、流体を濾過するために用いられる筒状フィルターであり、主として、水、油、塗料、界面活性剤等の液体を濾過するための筒状フィルター及びその製造方法に関する。   The present invention relates to a cylindrical filter used for filtering fluid, and mainly relates to a cylindrical filter for filtering liquids such as water, oil, paint, and surfactant, and a method for manufacturing the same.

従来、濾過層の構成成分として繊維を用いた筒状フィルターは、濾過対象液が、中空円筒状に形成された濾過層の最外周部から中心部に集められる間に、濾過層により濾過対象液中の微粒子を捕捉できるように構成されている。   Conventionally, a cylindrical filter using fibers as a constituent component of a filtration layer has a filtration target liquid collected by the filtration layer while the filtration target liquid is collected from the outermost periphery of the filtration layer formed in a hollow cylindrical shape to the center. It is comprised so that the microparticles | fine-particles in it can be captured.

このような筒状フィルターは、製薬工業、電子工業等における精製水の濾過、飲料水製造工程内における飲料水の濾過、自動車工業における塗装剤の濾過等、各種産業界において広く利用されている。   Such cylindrical filters are widely used in various industries such as filtration of purified water in the pharmaceutical industry, electronics industry, etc., filtration of drinking water in the manufacturing process of drinking water, and filtration of coating agents in the automobile industry.

上記のような分野に使用されてきた筒状フィルターとしては、例えば特許文献1や特許文献2等に提案された筒状フィルターが知られている。特許文献1では、ステープル繊維をカードで開繊して熱接着性複合繊維のウェブとし、このウェブを加熱しながら巻回し、複合繊維の低融点成分で熱接着して筒状フィルターを形成している。また、特許文献2では、スパンボンド不織布製造手法により得られたウェブを用いて、特許文献1の場合と同様に筒状フィルターを形成している。これらの筒状フィルターでは、熱接着性複合繊維が使用されており、濾過圧の上昇によっても熱接着された繊維間の剥離が起こり難いため、安定した捕捉精度が得られるといった利点がある。   As cylindrical filters that have been used in the above fields, for example, cylindrical filters proposed in Patent Document 1, Patent Document 2, and the like are known. In Patent Document 1, a staple fiber is opened with a card to form a heat-adhesive composite fiber web, the web is wound while being heated, and a low-melting component of the composite fiber is thermally bonded to form a cylindrical filter. Yes. Moreover, in patent document 2, the cylindrical filter is formed similarly to the case of patent document 1 using the web obtained by the spun bond nonwoven fabric manufacturing method. In these cylindrical filters, heat-adhesive conjugate fibers are used, and separation between the heat-bonded fibers hardly occurs even when the filtration pressure is increased, so that there is an advantage that stable capturing accuracy can be obtained.

また、特許文献3には、メルトブロー紡糸をしながら繊維径を変化させて堆積して得られた極細複合繊維ウェブを、熱処理して巻芯に巻き取った後、巻芯を抜き取ることによって得られた筒状フィルターが提案されている。   Further, Patent Document 3 is obtained by heat-treating an ultrafine composite fiber web obtained by changing the fiber diameter while melt blow spinning and winding the wound core around the core, and then extracting the core. A cylindrical filter has been proposed.

更に、特許文献4には、熱融着性複合繊維を含む繊維集合層を熱融着温度に加熱し、巻芯に巻き付け、引き続き所望の穴径を有するシート(例えば、濾紙、メンブレンフィルター等)を繊維集合層とともに巻き込んで精密濾過層を形成した後、繊維集合層のみを巻き取って前濾過層を形成し、冷却後巻芯を抜き取って得られた精密濾過用筒状フィルターが提案されている。
特開昭52−152575号公報 特開平8−226064号公報 特開平5−96110号公報 特公昭56−49605号公報
Further, Patent Document 4 discloses a sheet (for example, filter paper, membrane filter, etc.) having a desired hole diameter after heating a fiber assembly layer containing a heat-fusible conjugate fiber to a heat-fusing temperature and winding it around a winding core. After forming a microfiltration layer by winding together with a fiber assembly layer, a cylindrical filter for microfiltration obtained by winding only the fiber assembly layer to form a pre-filtration layer and extracting the core after cooling has been proposed. Yes.
JP-A-52-152575 JP-A-8-222604 JP-A-5-96110 Japanese Patent Publication No.56-49605

しかしながら上記のような従来の技術には以下のような問題点があった。まず、特許文献1の筒状フィルターは、構成繊維同士が強固に熱接着されているために、繊維間に形成される空隙が小さくなり、その結果、目詰まりが早くなる(即ち、濾過ライフが短くなる)という問題があった。また、繊維処理剤を用いて製造されるステープル繊維から構成されているため、濾過中に濾過対象液の泡立ちが発生するおそれがあった。   However, the conventional techniques as described above have the following problems. First, in the cylindrical filter of Patent Document 1, since the constituent fibers are firmly heat-bonded to each other, the gap formed between the fibers is reduced, and as a result, clogging is accelerated (that is, the filtration life is increased). There was a problem of shortening. Moreover, since it is comprised from the staple fiber manufactured using a fiber processing agent, there existed a possibility that foaming of the filtration object liquid might generate | occur | produce during filtration.

特許文献2の筒状フィルターは、繊維処理剤を用いずに製造されるスパンボンド不織布
を使用しているため、濾過中に濾過対象液の泡立ちが発生するおそれはない。また、スパンボンド不織布は繊維密度が高いため、特許文献1の筒状フィルターに比べ捕捉精度が良くなる。しかし、繊維密度が高い分、筒状フィルターの内部へ濾過対象液を送り込み難くなるため、筒状フィルターの表面のみで濾過する傾向が強くなり、濾過ライフが短くなるおそれがあった。
Since the cylindrical filter of patent document 2 uses the spunbonded nonwoven fabric manufactured without using a fiber processing agent, there is no possibility that foaming of the filtration object liquid may generate | occur | produce during filtration. In addition, since the spunbonded nonwoven fabric has a high fiber density, the capture accuracy is improved as compared with the cylindrical filter of Patent Document 1. However, the higher the fiber density, the more difficult it is to send the liquid to be filtered into the cylindrical filter, so that the tendency to filter only on the surface of the cylindrical filter increases, and the filtration life may be shortened.

特許文献3の筒状フィルターは、1dtex以下の極細繊維で構成されているために繊維間の空隙が小さくなり、濾過ライフが短くなる問題があった。   Since the cylindrical filter of patent document 3 is comprised by the ultrafine fiber of 1 dtex or less, there existed a problem that the space | gap between fibers became small and the filtration life became short.

特許文献4の筒状フィルターは、前濾過層の繊維間に形成される空隙が小さい上、精密濾過層が熱融着繊維層の中に押圧された状態で存在するため、筒状フィルターの表面のみで濾過する傾向が強くなり、特許文献2の筒状フィルターと同様に濾過ライフが短くなる問題があった。   The cylindrical filter of Patent Document 4 has a small gap formed between the fibers of the pre-filtration layer, and the microfiltration layer exists in a state of being pressed into the heat-bonded fiber layer. There was a problem that the tendency to filter alone became strong, and the filtration life was shortened similarly to the cylindrical filter of Patent Document 2.

本発明は、前記従来の問題を解決するため、濾過対象液の泡立ちを防ぐことができる上、濾過ライフの向上が可能な筒状フィルターとその製造方法を提供する。   In order to solve the above-described conventional problems, the present invention provides a cylindrical filter capable of preventing foaming of a filtration target liquid and improving a filtration life and a method for manufacturing the same.

本発明の筒状フィルターは、複数のスパンボンド不織布からなる複層不織布が巻回された筒状体を含み、隣り合う前記スパンボンド不織布同士が熱融着されている筒状フィルターであって、
前記筒状体において、隣り合う前記スパンボンド不織布のうち少なくとも一方は、第1熱可塑性樹脂と、前記第1熱可塑性樹脂より融点が10℃以上高い第2熱可塑性樹脂とを含む複合繊維からなり、
前記複層不織布において、隣り合う前記スパンボンド不織布の熱融着温度におけるそれぞれの熱収縮率の差が5%以上有り、かつ隣り合う前記スパンボンド不織布をそれぞれ構成する繊維の繊度が相違することを特徴とする。
The tubular filter of the present invention is a tubular filter including a tubular body wound with a multilayer nonwoven fabric composed of a plurality of spunbonded nonwoven fabrics, wherein the adjacent spunbonded nonwoven fabrics are heat-sealed,
In the cylindrical body, at least one of the adjacent spunbond nonwoven fabrics is composed of a composite fiber including a first thermoplastic resin and a second thermoplastic resin having a melting point higher than that of the first thermoplastic resin by 10 ° C. or more. ,
In the multilayer nonwoven fabric, there is a difference of 5% or more in each thermal shrinkage rate at the heat fusion temperature between the adjacent spunbond nonwoven fabrics, and the fineness of the fibers constituting the adjacent spunbond nonwoven fabrics is different. Features.

本発明の筒状フィルターの製造方法は、
第1スパンボンド不織布と、前記第1スパンボンド不織布と重なり合う第2スパンボンド不織布とを含み、前記第1及び第2スパンボンド不織布のうち少なくとも一方は、第1熱可塑性樹脂と、前記第1熱可塑性樹脂より融点が10℃以上高い第2熱可塑性樹脂とを含む複合繊維からなり、前記第1及び第2スパンボンド不織布の熱融着温度におけるそれぞれの熱収縮率の差が5%以上有り、前記第1及び第2スパンボンド不織布をそれぞれ構成する繊維の繊度が相違する積層スパンボンド不織布を加熱することによって、各層間が熱融着された複層不織布を形成し、
前記複層不織布を、前記第1熱可塑性樹脂の融点より5℃下回る温度以上に加熱しながら巻芯に巻き取り、
巻き取られた前記複層不織布を冷却し、前記巻芯を抜き取って、前記複層不織布が巻回された筒状体を形成する筒状フィルターの製造方法である。
The manufacturing method of the cylindrical filter of the present invention is:
A first spunbond nonwoven fabric and a second spunbond nonwoven fabric overlapping the first spunbond nonwoven fabric, wherein at least one of the first and second spunbond nonwoven fabrics includes a first thermoplastic resin and the first heat. A composite fiber comprising a second thermoplastic resin having a melting point higher than that of the plastic resin by 10 ° C. or more, and there is a difference of 5% or more in the respective heat shrinkage rates at the heat fusion temperature between the first and second spunbond nonwoven fabrics, By heating the laminated spunbonded nonwoven fabrics having different finenesses of the fibers constituting the first and second spunbonded nonwoven fabrics, a multilayer nonwoven fabric in which each layer is thermally fused is formed,
The multilayer nonwoven fabric is wound around a core while being heated to a temperature of 5 ° C. or lower than the melting point of the first thermoplastic resin,
It is the manufacturing method of the cylindrical filter which cools the wound said multilayer nonwoven fabric, extracts the said core, and forms the cylindrical body by which the said multilayer nonwoven fabric was wound.

本発明の筒状フィルターによれば、スパンボンド不織布を使用しているため、濾過対象液の泡立ちを防ぐことができる。また、複層不織布において、隣り合うスパンボンド不織布の熱融着温度におけるそれぞれの熱収縮率の差が5%以上有るため、スパンボンド不織布同士を熱融着した際、熱収縮率が小さい方のスパンボンド不織布に皺が発生し、スパンボンド不織布間に空隙が形成される。更に、複層不織布において、隣り合うスパンボンド不織布をそれぞれ構成する繊維の繊度が相違するため、捕捉精度を維持した上、筒状フィルターの内部へ濾過対象液を容易に送り込むことができる。これにより、濾過対象液の通液性が向上し、目詰まりが抑制されるため、濾過ライフの向上が可能となる。   According to the cylindrical filter of the present invention, since the spunbond nonwoven fabric is used, foaming of the liquid to be filtered can be prevented. In addition, in the multilayer nonwoven fabric, there is a difference of 5% or more in each thermal shrinkage rate at the heat fusion temperature between adjacent spunbond nonwoven fabrics. Wrinkles occur in the spunbonded nonwoven fabric, and voids are formed between the spunbonded nonwoven fabric. Furthermore, since the fineness of the fibers constituting the adjacent spunbond nonwoven fabrics in the multilayer nonwoven fabric is different, the liquid to be filtered can be easily fed into the cylindrical filter while maintaining the capture accuracy. Thereby, the liquid permeability of the liquid to be filtered is improved and clogging is suppressed, so that the filtration life can be improved.

本発明の筒状フィルターは、複数のスパンボンド不織布からなる複層不織布が巻回された筒状体を含み、隣り合うスパンボンド不織布同士が熱融着されている筒状フィルターである。ここで、本明細書において「スパンボンド不織布」とは、長繊維(例えば繊維長が1m以上であり、一般的には繊維長が無限である繊維)からなる不織布のことを指す。よって、本発明の筒状フィルターに使用できる不織布は、所謂スパンボンド手法により得られた不織布は無論であるが、長繊維であれば、例えば噴流直紡型のメルトブロー手法により得られた不織布であってもよい。長繊維からなる不織布は、繊維処理剤を用いずに製造される。そのため、本発明の筒状フィルターによれば、濾過対象液の泡立ちを防ぐことができる上、筒状フィルターからの溶剤等の不純物の溶出を防止できる。なお、筒状体の径方向に積層された複層不織布の層数は、例えば、30〜2000とすればよい。また、複層不織布を構成するスパンボンド不織布の厚みは特に限定されず、例えば0.1〜2mmとすればよい。また、複層不織布を構成するスパンボンド不織布の枚数についても特に限定されず、2枚以上であればよい。   The cylindrical filter of the present invention is a cylindrical filter including a cylindrical body around which a multilayer nonwoven fabric made of a plurality of spunbonded nonwoven fabrics is wound, and adjacent spunbonded nonwoven fabrics are heat-sealed. As used herein, the term “spunbond nonwoven fabric” refers to a nonwoven fabric composed of long fibers (for example, fibers having a fiber length of 1 m or longer and generally infinite fiber length). Therefore, the nonwoven fabric that can be used for the cylindrical filter of the present invention is naturally a nonwoven fabric obtained by a so-called spunbond technique, but if it is a long fiber, it is a nonwoven cloth obtained by, for example, a jet direct spinning type melt blow technique. May be. A nonwoven fabric made of long fibers is produced without using a fiber treatment agent. Therefore, according to the cylindrical filter of the present invention, foaming of the liquid to be filtered can be prevented, and elution of impurities such as a solvent from the cylindrical filter can be prevented. In addition, the number of layers of the multilayer nonwoven fabric laminated | stacked on the radial direction of the cylindrical body should just be 30-2000, for example. Moreover, the thickness of the spunbond nonwoven fabric which comprises a multilayer nonwoven fabric is not specifically limited, For example, what is necessary is just to be 0.1-2 mm. Moreover, it does not specifically limit about the number of the spun bond nonwoven fabrics which comprise a multilayer nonwoven fabric, What is necessary is just two or more.

前記筒状体において、隣り合うスパンボンド不織布のうち少なくとも一方は、第1熱可塑性樹脂と、第1熱可塑性樹脂より融点が10℃以上高い第2熱可塑性樹脂とを含む複合繊維からなる。これにより、スパンボンド不織布同士を、第1熱可塑性樹脂により熱融着させることができる。第1熱可塑性樹脂と第2熱可塑性樹脂との融点の差が10℃未満では、熱融着時に第2熱可塑性樹脂が溶融し、前記複合繊維の形状が維持できなくなるおそれがある。なお、本発明の筒状フィルターは、隣り合うスパンボンド不織布のうち少なくとも一方が前記複合繊維からなる不織布であればよく、他方のスパンボンド不織布については、単一成分繊維からなるものでもよいし、複合繊維からなるものでもよい。   In the cylindrical body, at least one of the adjacent spunbond nonwoven fabrics is composed of a composite fiber including a first thermoplastic resin and a second thermoplastic resin having a melting point higher by 10 ° C. or more than the first thermoplastic resin. Thereby, spun bond nonwoven fabric can be heat-seal | fused by 1st thermoplastic resin. If the difference in melting point between the first thermoplastic resin and the second thermoplastic resin is less than 10 ° C., the second thermoplastic resin may melt at the time of heat fusion, and the shape of the composite fiber may not be maintained. In addition, the cylindrical filter of the present invention may be a nonwoven fabric in which at least one of the adjacent spunbond nonwoven fabrics is composed of the above-mentioned composite fiber, and the other spunbond nonwoven fabric may be composed of a single component fiber, It may be made of a composite fiber.

前記複層不織布においては、隣り合うスパンボンド不織布の熱融着温度におけるそれぞれの熱収縮率の差が5%以上有り、好ましくは7%以上有る。ここで、「熱融着温度」とは、第1熱可塑性樹脂の融点−5℃から第2熱可塑性樹脂の融点−10℃までの範囲において、隣り合うスパンボンド不織布の熱収縮率の差が5%以上となる温度を任意に選択したものである。これにより、スパンボンド不織布同士を熱融着した際、熱収縮率が小さい方のスパンボンド不織布に皺が発生し、スパンボンド不織布間に空隙が形成される。その結果、濾過対象液の通液性が向上し、目詰まりが抑制されるため、濾過ライフの向上が可能となる。なお、前記熱収縮率の差が5%未満では、前記効果が低下する。また、前記熱収縮率の差が80%を超えると、筒状フィルターの成形が困難となるおそれがあるため、前記熱収縮率の差は、80%以下であることが好ましく、50%以下であることがより好ましい。   In the multi-layer nonwoven fabric, the difference in thermal shrinkage at the heat fusion temperature between adjacent spunbond nonwoven fabrics is 5% or more, preferably 7% or more. Here, the “thermal fusion temperature” is the difference in thermal shrinkage between adjacent spunbonded nonwoven fabrics in the range from the melting point of the first thermoplastic resin to −5 ° C. to the melting point of the second thermoplastic resin to −10 ° C. The temperature of 5% or more is arbitrarily selected. Thereby, when the spunbonded nonwoven fabrics are heat-sealed, wrinkles are generated in the spunbonded nonwoven fabric having a smaller heat shrinkage rate, and voids are formed between the spunbonded nonwoven fabrics. As a result, the liquid permeability of the liquid to be filtered is improved and clogging is suppressed, so that the filtration life can be improved. In addition, the said effect will fall if the difference of the said heat contraction rate is less than 5%. Further, if the difference in heat shrinkage rate exceeds 80%, it may be difficult to form a cylindrical filter. Therefore, the difference in heat shrinkage rate is preferably 80% or less, and 50% or less. More preferably.

前記複層不織布においては、隣り合うスパンボンド不織布をそれぞれ構成する繊維の繊度が相違する。これにより、例えば、繊度の小さい方の繊維(以下、「第1繊維」ともいう)で構成されたスパンボンド不織布が、濾過対象液中の微粒子を捕捉する役割を果たし、繊度の大きい方の繊維(以下、「第2繊維」ともいう)で構成されたスパンボンド不織布が、濾過対象液を通液させる役割を果たすことにより、捕捉精度を維持した上、筒状フィルターの内部へ濾過対象液を容易に送り込むことができる。よって、筒状フィルターの表面から内部にかけて満遍なく使用することができるため、濾過ライフの向上が可能となる。なお、本発明の筒状フィルターは、第1繊維で構成されたスパンボンド不織布が、濾過対象液を通液させる役割を果たし、第2繊維で構成されたスパンボンド不織布が、濾過対象液中の微粒子を捕捉する役割を果たすものであってもよい。また、本発明の筒状フィルターは、第1及び第2繊維から選ばれる少なくとも一方が前記複合繊維であればよい。   In the said multilayer nonwoven fabric, the fineness of the fiber which comprises each adjacent spun bond nonwoven fabric differs. Thereby, for example, a spunbond nonwoven fabric composed of fibers with smaller fineness (hereinafter also referred to as “first fibers”) plays a role of capturing fine particles in the liquid to be filtered, and fibers with larger fineness. The spunbond nonwoven fabric composed of (hereinafter also referred to as “second fiber”) plays the role of allowing the liquid to be filtered to pass through, thereby maintaining the capture accuracy and allowing the liquid to be filtered to enter the cylindrical filter. Can be sent in easily. Therefore, since it can be used evenly from the surface of the cylindrical filter to the inside, the filtration life can be improved. In the cylindrical filter of the present invention, the spunbond nonwoven fabric composed of the first fibers plays a role of passing the liquid to be filtered, and the spunbond nonwoven fabric composed of the second fibers is in the liquid to be filtered. It may play a role of capturing fine particles. In the cylindrical filter of the present invention, at least one selected from the first and second fibers may be the composite fiber.

また、前記機能をより向上させるためには、第2繊維は、第1繊維に比べ、繊度が1.5倍以上であることが好ましく、2倍以上であることがより好ましい。この場合、第1繊維の繊度は、例えば0.5〜10dtexであればよく、第2繊維の繊度は、例えば3〜50dtexであればよい。なお、前記スパンボンド不織布が、繊度が相違する多数の単繊維からなる混繊スパンボンド不織布である場合、第1繊維又は第2繊維の繊度は、それぞれの単繊維の繊度を平均した平均繊度とする。   In order to further improve the function, the fineness of the second fiber is preferably 1.5 times or more, more preferably 2 times or more, as compared with the first fiber. In this case, the fineness of the first fiber may be, for example, 0.5 to 10 dtex, and the fineness of the second fiber may be, for example, 3 to 50 dtex. When the spunbond nonwoven fabric is a mixed fiber spunbond nonwoven fabric composed of a large number of single fibers having different finenesses, the fineness of the first fibers or the second fibers is an average fineness obtained by averaging the finenesses of the single fibers. To do.

通常、スパンボンド不織布は、熱延伸されておらず、配向結晶性が低いので、ステープル繊維に比べて腰がない。よって、これを巻回して筒状フィルターを形成すると、繊維密度が異常に高くなるため、濾過ライフの極めて短い筒状フィルターとなり、従来全く実用性がなかった。本発明は、上述した構成により、スパンボンド不織布を用いても、濾過ライフの長い筒状フィルターを提供することができる。   Usually, a spunbonded nonwoven fabric is not heat stretched and has low orientation crystallinity, so it is less stiff than staple fibers. Therefore, when this is wound to form a cylindrical filter, the fiber density becomes abnormally high, resulting in a cylindrical filter with an extremely short filtration life, which has never been practical. The present invention can provide a cylindrical filter having a long filtration life even when a spunbonded nonwoven fabric is used.

熱収縮率が小さい方のスパンボンド不織布を構成する繊維は、第1繊維であってもよいし、第2繊維であってもよい。一方のスパンボンド不織布を熱収縮させて他方のスパンボンド不織布に皺を発生させ見かけ上嵩高化することによって、繊維密度の低い複層不織布とすることができる。その結果、筒状フィルターの厚み方向において深層濾過が可能となり、濾過ライフが向上する。更に、前記複層不織布を巻回するときに、巻芯への押し圧を制御して筒状フィルターの内側を密にし、外側を粗にすることにより、深層濾過がより容易となり、濾過ライフがより向上する。   The fibers constituting the spunbonded nonwoven fabric having the smaller heat shrinkage rate may be the first fibers or the second fibers. By heat shrinking one spunbonded nonwoven fabric to generate wrinkles in the other spunbonded nonwoven fabric and apparently increase the bulk, a multilayer nonwoven fabric having a low fiber density can be obtained. As a result, depth filtration is possible in the thickness direction of the cylindrical filter, and the filtration life is improved. Furthermore, when the multilayer nonwoven fabric is wound, by controlling the pressure applied to the core to make the inside of the cylindrical filter dense and rough on the outside, depth filtration becomes easier and the filtration life is reduced. More improved.

熱収縮率が大きい方のスパンボンド不織布と、熱収縮率が小さい方のスパンボンド不織布との目付比(後者の不織布の目付/前者の不織布の目付)は、0.1〜10であることが好ましい。より好ましい目付比は、0.6〜5であり、最も好ましくは2〜5である。目付比を上記範囲内とすることにより、濾過に有効な皺を形成することができる。各々の目付は、10〜50g/m2であることが好ましく、地合いの点から15〜30g/m2であることがより好ましい。 The basis weight ratio of the spunbond nonwoven fabric having the larger heat shrinkage rate and the spunbond nonwoven fabric having the smaller heat shrinkage rate (weight of the latter nonwoven fabric / weight of the former nonwoven fabric) is 0.1 to 10. preferable. A more preferable basis weight ratio is 0.6-5, and most preferably 2-5. By setting the basis weight ratio within the above range, it is possible to form ridges effective for filtration. Each basis weight is preferably 10 to 50 g / m 2, and more preferably 15 to 30 g / m 2 from the viewpoint of formation.

本発明に用いるスパンボンド不織布は、耐圧強度の観点から、前記複合繊維からなるスパンボンド不織布を筒状体の総質量の30質量%以上含むことが好ましく、総質量の80質量%以上含むことがより好ましい。   The spunbonded nonwoven fabric used in the present invention preferably contains 30% by mass or more of the total mass of the tubular body, and 80% by mass or more of the total mass of the spunbonded nonwoven fabric composed of the above composite fibers, from the viewpoint of pressure resistance. More preferred.

また、本発明の筒状フィルターは、前記複層不織布が、第1スパンボンド不織布と、第1スパンボンド不織布を挟持する第2スパンボンド不織布とからなり、第2スパンボンド不織布が、前記複合繊維から構成されている筒状フィルターであってもよい。中間層となる第1スパンボンド不織布を第2スパンボンド不織布で保護した状態で、筒状体を形成することができるからである。また、前記構成においては、第1スパンボンド不織布を構成する繊維の繊度が、第2スパンボンド不織布を構成する繊維の繊度よりも小さいことが好ましい。より微細な微粒子を捕捉できる層(第1スパンボンド不織布)を保護した状態で、筒状体を形成することができるからである。   In the cylindrical filter of the present invention, the multilayer nonwoven fabric includes a first spunbond nonwoven fabric and a second spunbond nonwoven fabric sandwiching the first spunbond nonwoven fabric, and the second spunbond nonwoven fabric is the composite fiber. The cylindrical filter comprised from may be sufficient. This is because the cylindrical body can be formed in a state where the first spunbond nonwoven fabric serving as the intermediate layer is protected by the second spunbond nonwoven fabric. Moreover, in the said structure, it is preferable that the fineness of the fiber which comprises a 1st spunbond nonwoven fabric is smaller than the fineness of the fiber which comprises a 2nd spunbond nonwoven fabric. This is because the cylindrical body can be formed in a state where the layer (first spunbond nonwoven fabric) capable of capturing finer fine particles is protected.

また、本発明の筒状フィルターは、筒状体の外周に巻回された外装スパンボンド不織布を更に含み、前記外装スパンボンド不織布が、前記複合繊維からなり、かつ前記筒状体の外周に熱融着されている筒状フィルターであってもよい。これにより、外装スパンボンド不織布をプレフィルターとして使用できるため、濾過ライフをより向上させることができる。   The cylindrical filter of the present invention further includes an exterior spunbond nonwoven fabric wound around the outer periphery of the cylindrical body, the exterior spunbond nonwoven fabric is made of the composite fiber, and heat is applied to the outer periphery of the cylindrical body. A fused cylindrical filter may be used. Thereby, since the exterior spunbonded nonwoven fabric can be used as a prefilter, the filtration life can be further improved.

前記スパンボンド不織布を構成する繊維の原料としては、溶融紡糸性を有する熱可塑性樹脂であれば特に限定されず、例えば、ポリエチレン、ポリプロピレン、ポリメチルペンテン−1、エチレン−プロピレン共重合体、エチレン−ビニルアルコール共重合体、エチレン−酢酸ビニル共重合体等のポリオレフィン系重合体又はその共重合体、ポリエチレンテレフタレート、ポリブチレンテレフタレート等のポリエステル系重合体又はその共重合体、ポリアミド6、ポリアミド66、ポリアミド12等のポリアミド系重合体又はその共重合体等を使用することができる。   The raw material of the fibers constituting the spunbonded nonwoven fabric is not particularly limited as long as it is a thermoplastic resin having melt spinnability. For example, polyethylene, polypropylene, polymethylpentene-1, ethylene-propylene copolymer, ethylene- Polyolefin polymers such as vinyl alcohol copolymers, ethylene-vinyl acetate copolymers or copolymers thereof, polyester polymers such as polyethylene terephthalate and polybutylene terephthalate or copolymers thereof, polyamide 6, polyamide 66, polyamide A polyamide polymer such as 12 or a copolymer thereof can be used.

前記スパンボンド不織布を構成する繊維の断面形状は、円型、楕円型、三角型等特に限定されない。また、前記スパンボンド不織布を構成する繊維が前記複合繊維の場合、その断面形状は、芯鞘型、偏心芯鞘型、分割型、並列型等特に限定されない。   The cross-sectional shape of the fibers constituting the spunbonded nonwoven fabric is not particularly limited, such as a circular shape, an elliptical shape, and a triangular shape. Moreover, when the fiber which comprises the said spun bond nonwoven fabric is the said composite fiber, the cross-sectional shape is not specifically limited, such as a core-sheath type, an eccentric core-sheath type, a split type, and a parallel type.

前記複合繊維は、第1熱可塑性樹脂(低融点熱可塑性樹脂)で繊維表面の過半が占められている偏芯した又は同心の鞘芯型複合繊維が好ましい。この場合、芯成分の繊維断面形状は、円形、猫目型、クローバー型等の円形とは異なる形状(異型)等特に限定されない。なお、鞘成分の融点が芯成分の融点に比べ20℃以上低い場合、熱融着加工上より都合がよい。   The composite fiber is preferably an eccentric or concentric sheath-core type composite fiber in which a majority of the fiber surface is occupied by the first thermoplastic resin (low-melting point thermoplastic resin). In this case, the fiber cross-sectional shape of the core component is not particularly limited, for example, a shape (atypical shape) different from a circle, such as a circle, a cat-eye shape, or a clover shape. When the melting point of the sheath component is lower by 20 ° C. or more than the melting point of the core component, it is more convenient for heat fusion processing.

前記スパンボンド不織布を構成する繊維の原料として、ポリオレフィンを使用する場合は、230℃におけるMelt Flow Rate(MFR)が5〜40g/10分のポリオレフィンを用いると、比較的熱収縮率が小さいスパンボンド不織布が得られる。一方、MFRが100g/10分を超えるポリオレフィンを用いると、比較的熱収縮率が大きいスパンボンド不織布が得られる。なお、10dtexを超える太い繊維のスパンボンド不織布には、通常、ステープル繊維に使用するポリオレフィンか、これに近い低MFRの樹脂が用いられ、3dtex以下の細い繊維のスパンボンド不織布には、通常、高MFRの樹脂が用いられる。   When using polyolefin as a raw material of the fibers constituting the spunbonded nonwoven fabric, if a polyolefin having a Melt Flow Rate (MFR) at 230 ° C. of 5 to 40 g / 10 min is used, a spunbond having a relatively low heat shrinkage rate A non-woven fabric is obtained. On the other hand, when a polyolefin having an MFR exceeding 100 g / 10 min is used, a spunbonded nonwoven fabric having a relatively high heat shrinkage rate can be obtained. Polyolefins used for staple fibers or similar low MFR resins are generally used for spunbond nonwoven fabrics with thick fibers exceeding 10 dtex, and spunbond nonwoven fabrics with thin fibers of 3 dtex or less are usually high. An MFR resin is used.

また、エチレンープロピレン共重合体を鞘成分とする複合繊維からなるスパンボンド不織布を用いると、熱収縮率が大きくなる上、熱融着加工する時、捲縮して嵩高化するため好ましい。   In addition, it is preferable to use a spunbonded nonwoven fabric composed of a composite fiber having an ethylene-propylene copolymer as a sheath component, because the thermal shrinkage rate is increased and crimping and bulking are performed during heat fusion processing.

前記複合繊維の原料として、ポリエステルを使用する場合、比較的熱収縮率が大きいスパンボンド不織布が得られるため、これと組み合わせる他方のスパンボンド不織布としては、熱収縮率及び目付がより小さいスパンボンド不織布が好ましい。   When polyester is used as the raw material of the composite fiber, a spunbond nonwoven fabric having a relatively high heat shrinkage ratio is obtained. As the other spunbond nonwoven fabric combined with this, a spunbond nonwoven fabric having a smaller heat shrinkage ratio and basis weight is used. Is preferred.

耐酸、耐アルカリ性等の耐薬品性や、耐腐食性を重視する分野の筒状フィルターに最適な前記複合繊維としては、鞘成分を高密度ポリエチレン、中密度ポリエチレン、低密度ポリエチレン等のポリエチレン、エチレンープロピレン共重合体又はポリブテン−1とし、ポリプロピレンを芯成分とする芯鞘型複合繊維が好ましい。また、前記複合繊維からなるスパンボンド不織布と組み合わせるスパンボンド不織布として、単一成分繊維からなるスパンボンド不織布を使用する場合は、ポリプロピレンからなるスパンボンド不織布を使用すると経済的に好ましい。   As the above-mentioned composite fiber that is most suitable for cylindrical filters in the field where chemical resistance such as acid resistance and alkali resistance and corrosion resistance is important, polyethylene such as high density polyethylene, medium density polyethylene, and low density polyethylene, ethylene A core-sheath type composite fiber having a propylene copolymer or polybutene-1 and polypropylene as a core component is preferred. Moreover, when using the spunbond nonwoven fabric which consists of a single component fiber as a spunbond nonwoven fabric combined with the spunbond nonwoven fabric which consists of the said composite fiber, it is economically preferable to use the spunbond nonwoven fabric which consists of polypropylene.

100℃を超える温度における耐熱性が要求される分野の筒状フィルターには、全てポリエステルからなるスパンボンド不織布で構成されている筒状フィルターが好ましい。このうち、芯鞘型複合繊維からなるスパンボンド不織布を使用する場合、前記芯鞘型複合繊維の鞘成分は、脂肪族ポリエステル及びポリエステル共重合体からなる群から選ばれる少なくとも1種であって、融点又は流動開始温度が210℃以下となる樹脂であることが好ましく、前記芯鞘型複合繊維の芯成分は、ポリエチレンテレフタレート、ポリブチレンテレフタレート及びポリトリメチレンテレフタレートからなる群から選ばれる少なくとも1種であることが好ましい。複層不織布を熱接着させながら巻回して筒状フィルターとするとき、少なくとも鞘成分の融点又は流動開始温度以上に熱処理温度を高くする必要があるため、鞘成分の融点又は流動開始温度が210℃を超える場合は、前記熱処理温度が芯成分の融点又は軟化する温度を超えることとなり、筒状フィルターを作製することが困難となるおそれがある。前記脂肪族ポリエステルや、前記ポリエステル共重合体としては、例えば、脂肪族ジカルボン酸単独又は脂肪族ジカルボン酸と芳香族ジカルボン酸との混合物と、1種又は2種のジオールとを重合したものが挙げられる。また、前記複合繊維からなるスパンボンド不織布と組み合わせる他方のスパンボンド不織布として、単一成分繊維からなるスパンボンド不織布を使用する場合は、ポリエチレンテレフタレート、ポリブチレンテレフタレート及びポリトリメチレンテレフタレートからなる群から選ばれる少なくとも1種を用いて構成されたスパンボンド不織布を使用すると経済的に好ましい。   For a cylindrical filter in a field where heat resistance at a temperature exceeding 100 ° C. is required, a cylindrical filter composed of a spunbond nonwoven fabric made of polyester is preferred. Among these, when using a spunbond nonwoven fabric composed of a core-sheath type composite fiber, the sheath component of the core-sheath type composite fiber is at least one selected from the group consisting of an aliphatic polyester and a polyester copolymer, It is preferable that the resin has a melting point or a flow start temperature of 210 ° C. or less, and the core component of the core-sheath composite fiber is at least one selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, and polytrimethylene terephthalate. Preferably there is. When a multi-layer nonwoven fabric is wound while being thermally bonded to form a cylindrical filter, it is necessary to increase the heat treatment temperature to at least the melting point or flow start temperature of the sheath component, so the melting point or flow start temperature of the sheath component is 210 ° C. In the case of exceeding the above, the heat treatment temperature exceeds the melting point or softening temperature of the core component, which may make it difficult to produce a cylindrical filter. Examples of the aliphatic polyester and the polyester copolymer include those obtained by polymerizing an aliphatic dicarboxylic acid alone or a mixture of an aliphatic dicarboxylic acid and an aromatic dicarboxylic acid and one or two diols. It is done. In addition, as the other spunbond nonwoven fabric combined with the composite fiber spunbond nonwoven fabric, when using a spunbond nonwoven fabric composed of single component fibers, it is selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate and polytrimethylene terephthalate. It is economically preferable to use a spunbonded nonwoven fabric composed of at least one selected from the above.

本発明の筒状フィルターに単一成分繊維のスパンボンド不織布を用いる場合は、前記単一成分繊維が、ポイントボント等の熱接着、又はニードルパンチや水流交絡法による繊維交絡一体化固定によって不織布化されており、更に層剥離しない様に厚み方向においても固定されている不織布が好ましい。また、本発明の筒状フィルターに使用される複合繊維のスパンボンド不織布においては、これらに加え、熱風で複合繊維間が接着された不織布も好ましい。   When a single-component fiber spunbond nonwoven fabric is used for the cylindrical filter of the present invention, the single-component fiber is made into a nonwoven fabric by thermal bonding such as point bonding, or fiber entanglement integrated fixation by needle punching or hydroentanglement method. Further, a non-woven fabric that is fixed in the thickness direction so as not to delaminate further is preferable. Moreover, in the composite fiber spunbond nonwoven fabric used for the cylindrical filter of the present invention, in addition to these, a nonwoven fabric in which the composite fibers are bonded with hot air is also preferable.

また、本発明に使用されるスパンボンド不織布を構成する熱可塑性樹脂は、重合時に未反応のモノマーや低分子量のオリゴマーが残存する可能性があるため、スパンボンド不織布に、前記モノマーや前記オリゴマーが不純物として微少量残留する可能性がある。これら不純物を除去するため、スパンボンド手法や、噴流直紡型のメルトブロー手法で作られた長繊維ウェブを水流交絡処理して、繊維を水洗しながら不織布化するのが好ましい。無論、複層不織布とした後に、更に水流交絡処理して不純物の除去を行った後、筒状体に形成するのも好ましい。   In addition, since the thermoplastic resin constituting the spunbond nonwoven fabric used in the present invention may leave unreacted monomers and low molecular weight oligomers during polymerization, the monomers and the oligomers are present in the spunbond nonwoven fabric. A very small amount may remain as an impurity. In order to remove these impurities, it is preferable that a long fiber web made by a spunbond technique or a jet direct spinning type melt blow technique is hydroentangled to form a nonwoven fabric while washing the fibers with water. Of course, after forming a multilayer nonwoven fabric, it is also preferable to form it into a cylindrical body after further removing the impurities by hydroentanglement treatment.

次に、本発明の筒状フィルターの製造方法について説明する。なお、本発明の筒状フィルターの製造方法は、前述した本発明の筒状フィルターを製造するための好適な製造方法である。よって、以下に述べる各構成要素の材料等は、前述した本発明の筒状フィルターと同様である。   Next, the manufacturing method of the cylindrical filter of this invention is demonstrated. In addition, the manufacturing method of the cylindrical filter of this invention is a suitable manufacturing method for manufacturing the cylindrical filter of this invention mentioned above. Therefore, the material of each component described below is the same as that of the cylindrical filter of the present invention described above.

本発明の筒状フィルターの製造方法は、まず、2枚以上のスパンボンド不織布が積層された積層スパンボンド不織布を加熱し、各層間を熱融着させることによって複層不織布を形成する。前記積層スパンボンド不織布には、第1スパンボンド不織布と、第1スパンボンド不織布と重なり合う第2スパンボンド不織布とを含み、第1及び第2スパンボンド不織布のうち少なくとも一方が、第1熱可塑性樹脂と、第1熱可塑性樹脂より融点が10℃以上高い第2熱可塑性樹脂とを含む複合繊維からなり、第1及び第2スパンボンド不織布の熱融着温度におけるそれぞれの熱収縮率の差が5%以上有り、第1及び第2スパンボンド不織布をそれぞれ構成する繊維の繊度が相違するものを用いる。なお、熱融着させる際は、例えば第1熱可塑性樹脂の融点−5℃から第2熱可塑性樹脂の融点−10℃までの範囲内の加熱温度で加熱すればよい。   In the method for producing a cylindrical filter of the present invention, a multilayer nonwoven fabric is formed by first heating a laminated spunbond nonwoven fabric in which two or more spunbond nonwoven fabrics are laminated and thermally fusing each layer. The laminated spunbond nonwoven fabric includes a first spunbond nonwoven fabric and a second spunbond nonwoven fabric that overlaps the first spunbond nonwoven fabric, and at least one of the first and second spunbond nonwoven fabrics is a first thermoplastic resin. And a second thermoplastic resin having a melting point higher than that of the first thermoplastic resin by 10 ° C. or more, and the difference in thermal shrinkage between the first and second spunbonded nonwoven fabrics at the heat fusion temperature is 5 % Or more, and fibers having different finenesses constituting the first and second spunbond nonwoven fabrics are used. In addition, what is necessary is just to heat at the heating temperature in the range from melting | fusing point-5 degreeC of a 1st thermoplastic resin to melting | fusing point-10 degreeC of a 2nd thermoplastic resin, for example, when making it heat-seal | fuse.

次に、得られた複層不織布を、第1熱可塑性樹脂の融点より5℃下回る温度以上に加熱しながら巻芯に巻き取る。巻芯としては、例えば鉄芯等が使用できる。なお、第1熱可塑性樹脂の融点より5℃下回る温度未満では、形成される筒状体において、隣り合うスパンボンド不織布同士を熱融着させることできなくなる場合がある。また、加熱温度が、第2熱可塑性樹脂の融点−10℃を超えると、筒状フィルターの成形が困難となるおそれがあるため、加熱温度は第2熱可塑性樹脂の融点−10℃以下とするのが好ましい。   Next, the obtained multilayer nonwoven fabric is wound around a core while being heated to a temperature not lower than 5 ° C. below the melting point of the first thermoplastic resin. As the winding core, for example, an iron core or the like can be used. If the temperature is less than 5 ° C. below the melting point of the first thermoplastic resin, it may be impossible to heat-seal adjacent spunbond nonwoven fabrics in the formed cylindrical body. In addition, if the heating temperature exceeds the melting point of the second thermoplastic resin of −10 ° C., it may be difficult to mold the cylindrical filter. Therefore, the heating temperature is set to the melting point of the second thermoplastic resin of −10 ° C. or lower. Is preferred.

なお、複層不織布を巻芯に巻き取る際、熱融着させる箇所への押し圧の掛け方と程度は、得られる筒状フィルターの濾過ライフや、耐圧強度に大きく影響する。例えば、複層不織布を巻き上げる際、巻き上げシャフトの自重で押し付け、圧迫しながら巻き上げると、繊維密度が高くなって、濾過ライフの短いフィルターとなり易いので、巻き上げシャフトの押し圧を制御できる構造の巻き上げ設備を用いるのが好ましい。好適な巻き上げ設備の一例として、巻き上げシャフトが複層不織布を圧迫しないように、巻き上げシャフト全体を流体圧で持ち上げる機構が設けられた設備が挙げられる。また、好適な巻き上げ設備の別の一例として、巻き上げシャフトを複層不織布からなる筒状体の横方向から押し付けて、巻き上げシャフトの自重が前記筒状体に掛らないようにして巻き上げることができる設備が挙げられる。   In addition, when winding a multilayer nonwoven fabric around a winding core, how to apply the pressing pressure to the part to heat-seal and a grade have big influence on the filtration life of a cylindrical filter obtained, and a pressure-resistant intensity | strength. For example, when winding a multi-layered nonwoven fabric, it is pressed with the weight of the hoisting shaft, and if it is rolled up while being compressed, the fiber density becomes high and the filter tends to have a short filtration life. Is preferably used. As an example of a suitable hoisting equipment, there is an equipment provided with a mechanism for lifting the entire hoisting shaft with fluid pressure so that the hoisting shaft does not press the multilayer nonwoven fabric. Moreover, as another example of a suitable hoisting equipment, the hoisting shaft can be pushed from the lateral direction of the cylindrical body made of a multilayer nonwoven fabric so that the self-weight of the hoisting shaft is not applied to the cylindrical body. Equipment.

そして、巻き取られた複層不織布を冷却し、巻芯を抜き取って、複層不織布が巻回された筒状体を形成する。冷却する際は、例えば複層不織布の温度が前記複合繊維の鞘成分の軟化点以下となる温度まで、具体的には、例えば鞘成分がポリエチレン樹脂の場合は60℃程度以下になるまで、空冷等により冷却すればよい。   And the wound multilayer nonwoven fabric is cooled, a core is extracted, and the cylindrical body by which the multilayer nonwoven fabric was wound is formed. When cooling, for example, until the temperature of the multilayer nonwoven fabric is equal to or lower than the softening point of the sheath component of the composite fiber, specifically, for example, when the sheath component is a polyethylene resin, air cooling What is necessary is just to cool by etc.

次に、本発明の筒状フィルターについて図面を用いて説明する。参照する図1は、本発明の筒状フィルターの一例を示す斜視図である。また、参照する図2は、図1の筒状フィルターに使用される複層不織布を示す模式断面図である。   Next, the cylindrical filter of the present invention will be described with reference to the drawings. FIG. 1 to be referred to is a perspective view showing an example of a cylindrical filter of the present invention. Moreover, FIG. 2 to refer is a schematic cross section which shows the multilayer nonwoven fabric used for the cylindrical filter of FIG.

図1に示すように、筒状フィルター1は、複層不織布20が巻回された筒状体10を含む。   As shown in FIG. 1, the tubular filter 1 includes a tubular body 10 around which a multilayer nonwoven fabric 20 is wound.

図2に示すように、複層不織布20は、第1スパンボンド不織布21と、第1スパンボンド不織布21を挟持する第2スパンボンド不織布22とからなる。また、少なくとも第2スパンボンド不織布22は、第1熱可塑性樹脂と、第1熱可塑性樹脂より融点が10℃以上高い第2熱可塑性樹脂とを含む複合繊維からなり、第1スパンボンド不織布21と第2スパンボンド不織布22とは、第1熱可塑性樹脂成分により熱融着されている。   As shown in FIG. 2, the multilayer nonwoven fabric 20 includes a first spunbond nonwoven fabric 21 and a second spunbond nonwoven fabric 22 that sandwiches the first spunbond nonwoven fabric 21. Further, at least the second spunbond nonwoven fabric 22 is composed of a composite fiber including a first thermoplastic resin and a second thermoplastic resin having a melting point higher than that of the first thermoplastic resin by 10 ° C. or more. The second spunbond nonwoven fabric 22 is heat-sealed with the first thermoplastic resin component.

また、第1スパンボンド不織布21と第2スパンボンド不織布22とは、熱融着温度におけるそれぞれの熱収縮率の差が5%以上有る。これにより、第1スパンボンド不織布21と第2スパンボンド不織布22とを熱融着した際、熱収縮率が小さい方のスパンボンド不織布(図2の場合は第2スパンボンド不織布22)に皺22aが発生し、第1及び第2スパンボンド不織布21,22間に空隙SPが形成される。その結果、濾過対象液の通液性が向上し、目詰まりが抑制されるため、濾過ライフの向上が可能となる。   Further, the first spunbonded nonwoven fabric 21 and the second spunbonded nonwoven fabric 22 have a difference of 5% or more in the respective heat shrinkage rates at the heat fusion temperature. As a result, when the first spunbond nonwoven fabric 21 and the second spunbond nonwoven fabric 22 are heat-sealed, the spunbond nonwoven fabric (second spunbond nonwoven fabric 22 in the case of FIG. 2) having a smaller thermal shrinkage ratio is a ridge 22a. Is generated, and a gap SP is formed between the first and second spunbond nonwoven fabrics 21 and 22. As a result, the liquid permeability of the liquid to be filtered is improved and clogging is suppressed, so that the filtration life can be improved.

また、第1スパンボンド不織布21を構成する繊維と、第2スパンボンド不織布22を構成する繊維とは、繊度が相違している。例えば、第1スパンボンド不織布21が、繊度の小さい方の繊維(第1繊維)で構成され、第2スパンボンド不織布22が、繊度の大きい方の繊維(第2繊維)で構成されている場合は、第1スパンボンド不織布21が、濾過対象液中の微粒子を捕捉する役割を果たし、第2スパンボンド不織布22が、濾過対象液を通液させる役割を果たす。これにより、捕捉精度を維持した上、筒状フィルター1の内部へ濾過対象液を容易に送り込むことができる。よって、筒状フィルター1の表面から内部にかけて満遍なく使用することができるため、濾過ライフの向上が可能となる。また、前記構成の場合は、微粒子の捕捉層となる第1スパンボンド不織布21を第2スパンボンド不織布22で保護した状態で、筒状体10を形成することができる。   Further, the fibers constituting the first spunbond nonwoven fabric 21 and the fibers constituting the second spunbond nonwoven fabric 22 have different finenesses. For example, when the 1st spunbond nonwoven fabric 21 is comprised with the fiber (1st fiber) with a smaller fineness, and the 2nd spunbond nonwoven fabric 22 is comprised with the fiber (2nd fiber) with a larger fineness. The first spunbond nonwoven fabric 21 plays a role of capturing fine particles in the filtration target liquid, and the second spunbond nonwoven fabric 22 plays a role of passing the filtration target liquid. As a result, the liquid to be filtered can be easily fed into the cylindrical filter 1 while maintaining the capture accuracy. Therefore, since it can be used uniformly from the surface of the cylindrical filter 1 to the inside, the filtration life can be improved. Moreover, in the case of the said structure, the cylindrical body 10 can be formed in the state which protected the 1st spunbond nonwoven fabric 21 used as the capture layer of microparticles | fine-particles with the 2nd spunbond nonwoven fabric 22. FIG.

なお、空隙SPが形成された複層不織布20の厚みT(以下、「見かけ厚み」という)は、空隙SPが形成されない場合(それぞれの熱収縮率に差が無い場合)の厚みに比べ、例えば1.5〜8倍程度であり、より好ましくは2〜8倍程度である。   In addition, the thickness T (hereinafter referred to as “apparent thickness”) of the multilayer nonwoven fabric 20 in which the void SP is formed is, for example, compared to the thickness when the void SP is not formed (when there is no difference in the respective thermal shrinkage rates). About 1.5 to 8 times, more preferably about 2 to 8 times.

以上、本発明の筒状フィルターについて説明したが、本発明はこれに限定されるものではない。例えば、複層不織布として、熱収縮率がより小さいスパンボンド不織布を、熱収縮率がより大きいスパンボンド不織布で挟持したものを使用してもよい。また、図3に示すように、筒状体10の外周に巻回された外装スパンボンド不織布30を更に含む筒状フィルターであって、外装スパンボンド不織布30が、前記複合繊維からなり、かつ筒状体10の外周に熱融着されている筒状フィルター2としてもよい。これにより、外装スパンボンド不織布30をプレフィルターとして使用できるため、濾過ライフをより向上させることができる。   Although the cylindrical filter of the present invention has been described above, the present invention is not limited to this. For example, a multi-layer nonwoven fabric in which a spunbond nonwoven fabric having a smaller heat shrinkage rate is sandwiched between spunbond nonwoven fabrics having a higher heat shrinkage rate may be used. Also, as shown in FIG. 3, the tubular filter further includes an exterior spunbond nonwoven fabric 30 wound around the outer periphery of the tubular body 10, wherein the exterior spunbond nonwoven fabric 30 is made of the above-described composite fiber and It is good also as the cylindrical filter 2 heat-sealed on the outer periphery of the shaped body 10. Thereby, since the exterior spunbond nonwoven fabric 30 can be used as a pre-filter, the filtration life can be further improved.

次に、本発明の筒状フィルターの製造方法について図面を用いて説明する。参照する図4A,Bは、本発明の筒状フィルターの製造方法の一例を示す模式工程図である。なお、図1及び図2と同一の構成要素には同一の符号を付し、その説明は省略する。   Next, the manufacturing method of the cylindrical filter of this invention is demonstrated using drawing. 4A and 4B to be referred to are schematic process diagrams showing an example of a method for producing a cylindrical filter of the present invention. The same components as those in FIGS. 1 and 2 are denoted by the same reference numerals, and the description thereof is omitted.

まず、図4Aに示すように、第1ロール50に巻回された第1スパンボンド不織布21と、第2ロール51に巻回された第2スパンボンド不織布22と、第3ロール52に巻回された第2スパンボンド不織布22とを、それぞれ送り出しながら積層して積層スパンボンド不織布23を形成し、この積層スパンボンド不織布23を熱処理機53により加熱することによって、各層間が熱融着された複層不織布20を形成する。そして、複層不織布20を巻き取りロール54にて巻き取る。なお、熱処理機53としては、例えば熱風加熱型の熱処理機が使用できる。   First, as shown in FIG. 4A, the first spunbond nonwoven fabric 21 wound around the first roll 50, the second spunbond nonwoven fabric 22 wound around the second roll 51, and the third roll 52 wound around The laminated second spunbond nonwoven fabric 22 was laminated while being fed out to form a laminated spunbond nonwoven fabric 23, and the laminated spunbond nonwoven fabric 23 was heated by a heat treatment machine 53, whereby the respective layers were thermally fused. The multilayer nonwoven fabric 20 is formed. Then, the multilayer nonwoven fabric 20 is wound up by the winding roll 54. As the heat treatment machine 53, for example, a hot air heating type heat treatment machine can be used.

続いて、図4Bに示すように、得られた複層不織布20を熱処理機55へと送り出して、熱処理機55にて、複層不織布20中の第1熱可塑性樹脂の融点より5℃下回る温度以上に加熱して、巻芯56に巻き取る。更に、図示はしないが、巻き取られた複層不織布20を冷却し、巻芯56を抜き取って、複層不織布20が巻回された筒状体10(図1参照)を形成する。なお、熱処理機55としては、例えば熱風加熱型の熱処理機、赤外線加熱型の熱処理機、熱風・赤外線加熱併用型の熱処理機等が使用できる。また、第2スパンボンド不織布22の皺22a(図2参照)は、熱処理機53による加熱工程及び熱処理機55による加熱工程のうち、少なくともいずれか一方で形成されればよい。   Subsequently, as shown in FIG. 4B, the obtained multilayer nonwoven fabric 20 is sent to a heat treatment machine 55, and the heat treatment machine 55 is a temperature 5 ° C. lower than the melting point of the first thermoplastic resin in the multilayer nonwoven fabric 20. It heats above and winds up to the core 56. FIG. Furthermore, although not illustrated, the wound multilayer nonwoven fabric 20 is cooled, the core 56 is extracted, and the cylindrical body 10 (refer FIG. 1) by which the multilayer nonwoven fabric 20 was wound is formed. As the heat treatment machine 55, for example, a hot air heating type heat treatment machine, an infrared heating type heat treatment machine, a hot air / infrared heating combined heat treatment machine, or the like can be used. Further, the ridge 22a (see FIG. 2) of the second spunbond nonwoven fabric 22 may be formed by at least one of a heating process by the heat treatment machine 53 and a heating process by the heat treatment machine 55.

以上、本発明の筒状フィルターの製造方法について説明したが、本発明はこれに限定されるものではない。例えば、前記実施形態では、複層不織布の作製と、筒状体の作製とを別工程で行ったが、同一工程(オンライン)で行ってもよい。   As mentioned above, although the manufacturing method of the cylindrical filter of this invention was demonstrated, this invention is not limited to this. For example, in the above embodiment, the production of the multilayer nonwoven fabric and the production of the cylindrical body are performed in separate steps, but may be performed in the same step (online).

以下、本発明の実施例について説明する。なお、本発明は、以下の実施例に限定されるものではない。   Examples of the present invention will be described below. The present invention is not limited to the following examples.

[実施例1〜8及び比較例1,2]
(複層不織布の作製)
まず、表1に示す不織布A〜I(いずれも幅が約90cmのドット熱接着スパンボンド不織布)を用意した。このうち、不織布A〜Dは、芯成分がポリプロピレン(PP、融点:166℃)、鞘成分が高密度ポリエチレン(PE、融点:132℃)の芯鞘型複合繊維からなるスパンボンド不織布である。また、不織布Eは、芯成分がPP、鞘成分がポリブテン−1(PB、融点:128℃)の芯鞘型複合繊維からなるスパンボンド不織布である。また、不織布Fは、芯成分がPP、鞘成分がエチレンープロピレン共重合体(EP、融点:132℃)の芯鞘型複合繊維からなるスパンボンド不織布である。また、不織布G〜Iは、PPのみで構成された単一成分繊維からなるスパンボンド不織布である。そして、これらの不織布A〜Iを、表2に示す構成となるように組み合わせて積層スパンボンド不織布を形成し、この積層スパンボンド不織布を、拘束せずに熱収縮できる状態で熱風加熱型のコンベアー式熱処理機により加熱した(加熱温度:140℃)。この際の加工条件は、加工速度が15m/分、コンベアー式熱処理機内における滞留時間が20秒であった。この加熱により、スパンボンド不織布同士が熱融着された複層不織布が得られた。なお、表1に示す熱収縮率の値は、不織布A〜Iのそれぞれについて、加熱前の幅をAcmとし、140℃で20秒間加熱した後の幅をBcmとした場合の100×(A−B)/Aで算出される値とした。
[Examples 1 to 8 and Comparative Examples 1 and 2]
(Production of multilayer nonwoven fabric)
First, non-woven fabrics A to I shown in Table 1 (all are dot-bonded spunbond nonwoven fabrics having a width of about 90 cm) were prepared. Among these, the nonwoven fabrics A to D are spunbonded nonwoven fabrics composed of core-sheath type composite fibers whose core component is polypropylene (PP, melting point: 166 ° C.) and whose sheath component is high-density polyethylene (PE, melting point: 132 ° C.). The nonwoven fabric E is a spunbonded nonwoven fabric composed of a core-sheath type composite fiber having a core component of PP and a sheath component of polybutene-1 (PB, melting point: 128 ° C.). The nonwoven fabric F is a spunbonded nonwoven fabric composed of core-sheath type composite fibers in which the core component is PP and the sheath component is an ethylene-propylene copolymer (EP, melting point: 132 ° C.). Nonwoven fabrics GI are spunbonded nonwoven fabrics composed of single component fibers composed only of PP. And these nonwoven fabrics A-I are combined so that it may become the structure shown in Table 2, and a lamination | stacking spunbond nonwoven fabric is formed, and this lamination | stacking spunbond nonwoven fabric is a hot-air heating type conveyor in the state which can be thermally shrunk without restraint. It heated by the type | formula heat processing machine (heating temperature: 140 degreeC). The processing conditions at this time were a processing speed of 15 m / min and a residence time in the conveyor type heat treatment machine of 20 seconds. By this heating, a multilayer nonwoven fabric in which spunbonded nonwoven fabrics were heat-sealed was obtained. In addition, the value of the thermal contraction rate shown in Table 1 is 100 × (A− when the width after heating at 140 ° C. for 20 seconds is Bcm for each of the nonwoven fabrics A to I. B) / A.

Figure 2006150222
Figure 2006150222

Figure 2006150222
Figure 2006150222

(筒状フィルターの作製)
得られた複層不織布を、約30cm幅にスリットして、熱風・赤外線加熱併用型のコンベアー式熱処理機により加熱し(加熱温度:140℃)、鉄芯(長さ:32cm、直径:25mm)に、巻径が55mmに達するまで巻き取った。そして、巻き取られた複層不織布を冷却し、鉄芯を抜き取った後、両端を切断し、この切断面を、加熱した平板(表面温度:138℃)に押し当てることにより切断面の樹脂同士を融着させて、長さ250mmの筒状フィルターを作製した。
(Production of cylindrical filter)
The obtained multilayer nonwoven fabric is slit into a width of about 30 cm and heated by a hot air / infrared heating combined conveyor type heat treatment machine (heating temperature: 140 ° C.), iron core (length: 32 cm, diameter: 25 mm) And wound up until the winding diameter reached 55 mm. And after cooling the wound multilayer nonwoven fabric and pulling out an iron core, both ends are cut | disconnected and this cut surface is pressed against the heated flat plate (surface temperature: 138 degreeC), and resin of a cut surface is obtained. Were fused to produce a cylindrical filter having a length of 250 mm.

次に、得られた筒状フィルターの性能を評価した。結果を表2に示す。なお、2dtexのステープル製筒状フィルター(参考例1)、及び不織布Aのみを巻回して作製した筒状フィルター(参考例2)についても、同様に評価した(参考例2は濾過ライフのみ)。評価方法は以下のとおりである。   Next, the performance of the obtained cylindrical filter was evaluated. The results are shown in Table 2. A 2 dtex staple cylindrical filter (Reference Example 1) and a cylindrical filter (Reference Example 2) produced by winding only the nonwoven fabric A were also evaluated in the same manner (Reference Example 2 has only a filtration life). The evaluation method is as follows.

[捕捉精度]
JIS Z8901に準ずる試験用ダスト(JIS7種[中位径:27〜31μm]とJIS8種[中位径:6.6〜8.6μm]を1:1の質量割合で混合したもの、関東ローム製)の試験用懸濁液(濃度:50ppm)を、均一に攪拌しながら筒状フィルターの外側から中空部に向かって40リットル/分の流量で流し、濾過開始から5分経過した後の濾過液について評価した。評価方法は、まず、濾過前の試験用懸濁液の所定量に含まれるダストの粒子径別の個数(M)と、これを濾過した後の濾過液の所定量に残るダストの粒子径別の個数(N)とを粒度分布測定機(商品名:コールターカウンターZM型、コールターエレクトロニクス社製)を用いて測定した。次に、各粒子径別に遮断率(100×(M−N)/M)を算出した。そして、遮断率が99%になる粒子径(μm)を捕捉精度とした。なお、捕捉精度(μm)が小さい値になるほど、筒状フィルターが微小な粒子を補足できるようになる。
[Acquisition accuracy]
Dust for testing according to JIS Z8901 (mixed JIS 7 [median diameter: 27 to 31 μm] and JIS 8 [median diameter: 6.6 to 8.6 μm] in a mass ratio of 1: 1, manufactured by Kanto Loam ) Test suspension (concentration: 50 ppm) was flowed at a flow rate of 40 liters / minute from the outside of the cylindrical filter toward the hollow part with uniform stirring, and the filtrate after 5 minutes had passed since the start of filtration. Was evaluated. In the evaluation method, first, the number (M) of each dust particle size included in the predetermined amount of the test suspension before filtration, and the dust particle size remaining in the predetermined amount of the filtrate after filtration. Was measured using a particle size distribution analyzer (trade name: Coulter Counter ZM, manufactured by Coulter Electronics Co., Ltd.). Next, the blocking rate (100 × (MN) / M) was calculated for each particle size. The particle size (μm) at which the blocking rate was 99% was taken as the capture accuracy. Note that the smaller the capture accuracy (μm), the more the cylindrical filter can capture fine particles.

[通水圧損]
水を筒状フィルターの外側から中空部に向かって40L/分の流量で通水した時の、筒状フィルターの入口と筒状フィルターの出口との圧力差を測定した。
[Water pressure loss]
The pressure difference between the inlet of the cylindrical filter and the outlet of the cylindrical filter when water was passed from the outside of the cylindrical filter toward the hollow portion at a flow rate of 40 L / min was measured.

[濾過ライフ]
JIS Z8901に準ずる試験用ダスト(JIS8種[中位径:6.6〜8.6μm]とJIS11種[中位径:1.6〜2.3μm]を1:1の質量割合で混合したもの、関東ローム製)の試験用懸濁液(濃度:200ppm)を、均一に攪拌しながら筒状フィルターの外側から中空部に向かって15リットル/分の流量で流し、この流量を維持するための通液圧力が0.2MPaになったときの総通液量(リットル)で評価した。
[Filtration life]
Dust for testing according to JIS Z8901 (mixture of JIS 8 types [median diameter: 6.6 to 8.6 μm] and JIS 11 types [median diameter: 1.6 to 2.3 μm] in a mass ratio of 1: 1. In order to maintain this flow rate, a suspension for testing (concentration: 200 ppm) of Kanto Loam is flowed at a flow rate of 15 liters / minute from the outside of the cylindrical filter toward the hollow portion with uniform stirring. Evaluation was made based on the total flow rate (liter) when the flow rate was 0.2 MPa.

表2に示すように、不織布間の熱収縮率の差が5%以上有る実施例1〜8は、前記差が1%である比較例1に比べ、濾過ライフが向上した。また、実施例8と比較例2とを比較した場合に、いずれも濾過ライフは1000リットル以上であるが、捕捉精度に関しては、実施例8が比較例2に比べ大幅に向上した。   As shown in Table 2, in Examples 1 to 8 in which the difference in thermal shrinkage between the nonwoven fabrics was 5% or more, the filtration life was improved as compared with Comparative Example 1 in which the difference was 1%. Moreover, when Example 8 and Comparative Example 2 were compared with each other, the filtration life was 1000 liters or more. However, with regard to the capture accuracy, Example 8 was significantly improved compared to Comparative Example 2.

また、実施例1〜8の筒状フィルターの一部を削り取って、繊維処理剤(界面活性剤)の付着の有無を調べたが、当然のことながら検出できず、通水しても通過液の発泡は全くなかった。なお、実施例1〜8の筒状フィルターについて、メタノール抽出(JIS L 1015−7.22(6))を行った結果、いずれも0.02質量%の質量減少が生じた。これは、繊維表面に析出したオリゴマーが除去されたことによるものと考えられる。そこで、実施例1で使用した複層不織布に、高圧水流(2.94MPa)を噴射して水洗し、乾燥した後、上述の方法により筒状フィルターとし、同様にメタノール抽出を行ったところ、0.005質量%未満の質量減少となり、質量減少はほとんど観察されなかった。   Further, a part of the cylindrical filter of Examples 1 to 8 was scraped to examine the presence or absence of adhesion of the fiber treatment agent (surfactant). There was no foaming. In addition, about the cylindrical filter of Examples 1-8, as a result of performing methanol extraction (JIS L 1015-7.22 (6)), mass reduction of 0.02 mass% produced all. This is considered to be due to the removal of the oligomer deposited on the fiber surface. Therefore, the multilayer nonwoven fabric used in Example 1 was sprayed with a high-pressure water flow (2.94 MPa), washed with water, dried, and then formed into a cylindrical filter by the above-described method. The mass decreased to less than 0.005% by mass, and almost no mass decrease was observed.

また、前述した濾過ライフの評価を行った後の実施例1〜8の筒状フィルターを観察したところ、中心の空洞近くまで、試験用懸濁液の色(茶色)に着色していた。この結果から、実施例1〜8の筒状フィルターは、表面から内部にかけて満遍なく使用することができることが明らかになった。一方、濾過ライフの評価を行った後の比較例1の筒状フィルターは、外周から5mm程度までしか着色していなかった。   Moreover, when the cylindrical filter of Examples 1-8 after performing the evaluation of the filtration life mentioned above was observed, it was colored to the color (brown) of the suspension for a test to near the center cavity. From this result, it became clear that the cylindrical filters of Examples 1 to 8 can be used evenly from the surface to the inside. On the other hand, the cylindrical filter of Comparative Example 1 after the evaluation of the filtration life was colored only up to about 5 mm from the outer periphery.

また、参考例2の筒状フィルターは、質量が250gであったが、実施例1の筒状フィルターは、参考例1の筒状フィルターと同程度の200g前後の質量となり、嵩高さが向上した。   In addition, the cylindrical filter of Reference Example 2 had a mass of 250 g, but the cylindrical filter of Example 1 had a mass of about 200 g, which was the same as the cylindrical filter of Reference Example 1, and the bulkiness was improved. .

[実施例9]
次に、前述した筒状フィルター2(図3参照)の実施例である実施例9について説明する。実施例9の筒状フィルターは、実施例1の筒状フィルターの外周に不織布Aを熱融着させて形成した。具体的な形成方法は、まず、実施例1の筒状フィルターの外面に向かって不織布Aの先端部を押し当てて、金属ゴテ(表面温度:138℃)を用いてそれらを熱圧着した。次いで、実施例1の筒状フィルターを回転させて不織布Aを巻き付けながら(3周分)、最外周の不織布Aに、複数のフランジが設けられた金属棒(表面温度:138℃)を押し当てることにより、実施例1の筒状フィルターの外周に不織布Aを熱融着させて実施例9の筒状フィルターを形成した。
[Example 9]
Next, an embodiment 9 which is an embodiment of the above-described cylindrical filter 2 (see FIG. 3) will be described. The cylindrical filter of Example 9 was formed by thermally bonding the nonwoven fabric A to the outer periphery of the cylindrical filter of Example 1. Specifically, first, the tip of the nonwoven fabric A was pressed against the outer surface of the cylindrical filter of Example 1, and they were thermocompression bonded using a metal iron (surface temperature: 138 ° C.). Next, while rotating the tubular filter of Example 1 and winding the nonwoven fabric A (for three laps), a metal rod (surface temperature: 138 ° C.) provided with a plurality of flanges is pressed against the outermost nonwoven fabric A. Thereby, the nonwoven fabric A was heat-sealed to the outer periphery of the cylindrical filter of Example 1, and the cylindrical filter of Example 9 was formed.

次に、実施例9の筒状フィルターについて、その性能を実施例1と同様に評価したところ、実施例1と全く同様であった。ただし、試験用ダストとして、粒子径がより大きいものを用いれば、外装スパンボンド不織布(不織布A)が設けられた実施例9の筒状フィルターは、実施例1の筒状フィルターよりも濾過ライフ等の性能が向上するものと考えられる。   Next, when the performance of the cylindrical filter of Example 9 was evaluated in the same manner as in Example 1, it was exactly the same as in Example 1. However, if a dust having a larger particle size is used as the test dust, the tubular filter of Example 9 provided with the exterior spunbonded nonwoven fabric (nonwoven fabric A) has a filtration life or the like than the tubular filter of Example 1. It is thought that the performance of this will improve.

本発明の筒状フィルターは、製薬工業、電子工業等における精製水の濾過、飲料水製造工程内における飲料水の濾過、自動車工業における塗装剤の濾過等、様々な用途に使用することができる。   The cylindrical filter of the present invention can be used for various applications such as filtration of purified water in the pharmaceutical industry, electronics industry, etc., filtration of drinking water in the drinking water production process, and filtration of coating agents in the automobile industry.

本発明の筒状フィルターの一例を示す斜視図である。It is a perspective view which shows an example of the cylindrical filter of this invention. 図1の筒状フィルターに使用される複層不織布を示す模式断面図である。It is a schematic cross section which shows the multilayer nonwoven fabric used for the cylindrical filter of FIG. 本発明の筒状フィルターの別の一例を示す斜視図である。It is a perspective view which shows another example of the cylindrical filter of this invention. A,Bは、本発明の筒状フィルターの製造方法の一例を示す模式工程図である。A and B are schematic process diagrams showing an example of a method for producing a cylindrical filter of the present invention.

符号の説明Explanation of symbols

1,2 筒状フィルター
10 筒状体
20 複層不織布
21 第1スパンボンド不織布
22 第2スパンボンド不織布
23 積層スパンボンド不織布
30 外装スパンボンド不織布
56 巻芯
DESCRIPTION OF SYMBOLS 1, 2 Tubular filter 10 Tubular body 20 Multi-layer nonwoven fabric 21 First spunbond nonwoven fabric 22 Second spunbond nonwoven fabric 23 Laminated spunbond nonwoven fabric 30 Exterior spunbond nonwoven fabric 56 Core

Claims (9)

複数のスパンボンド不織布からなる複層不織布が巻回された筒状体を含み、隣り合う前記スパンボンド不織布同士が熱融着されている筒状フィルターであって、
前記筒状体において、隣り合う前記スパンボンド不織布のうち少なくとも一方は、第1熱可塑性樹脂と、前記第1熱可塑性樹脂より融点が10℃以上高い第2熱可塑性樹脂とを含む複合繊維からなり、
前記複層不織布において、隣り合う前記スパンボンド不織布の熱融着温度におけるそれぞれの熱収縮率の差が5%以上有り、かつ隣り合う前記スパンボンド不織布をそれぞれ構成する繊維の繊度が相違することを特徴とする筒状フィルター。
A cylindrical filter comprising a cylindrical body wound with a multilayer nonwoven fabric composed of a plurality of spunbonded nonwoven fabrics, wherein the adjacent spunbonded nonwoven fabrics are heat-sealed,
In the cylindrical body, at least one of the adjacent spunbond nonwoven fabrics is composed of a composite fiber including a first thermoplastic resin and a second thermoplastic resin having a melting point higher than that of the first thermoplastic resin by 10 ° C. or more. ,
In the multilayer nonwoven fabric, there is a difference of 5% or more in each thermal shrinkage rate at the heat fusion temperature between the adjacent spunbond nonwoven fabrics, and the fineness of the fibers constituting the adjacent spunbond nonwoven fabrics is different. Characteristic cylindrical filter.
前記複層不織布において、隣り合う前記スパンボンド不織布を構成する繊維のうち、より繊度が大きいほうの繊維は、より繊度が小さいほうの繊維に比べ、繊度が1.5倍以上である請求項1に記載の筒状フィルター。   In the multilayer nonwoven fabric, among the fibers constituting the adjacent spunbond nonwoven fabric, the fiber having a larger fineness has a fineness of 1.5 times or more than the fiber having a smaller fineness. The cylindrical filter as described in 2. 前記複層不織布は、第1スパンボンド不織布と、前記第1スパンボンド不織布を挟持する第2スパンボンド不織布とからなり、
前記第2スパンボンド不織布は、前記複合繊維から構成されている請求項1に記載の筒状フィルター。
The multilayer nonwoven fabric comprises a first spunbond nonwoven fabric and a second spunbond nonwoven fabric sandwiching the first spunbond nonwoven fabric,
The cylindrical filter according to claim 1, wherein the second spunbonded nonwoven fabric is composed of the composite fiber.
前記第1スパンボンド不織布を構成する繊維の繊度は、前記第2スパンボンド不織布を構成する繊維の繊度よりも小さい請求項3に記載の筒状フィルター。   The cylindrical filter according to claim 3, wherein the fineness of the fibers constituting the first spunbonded nonwoven fabric is smaller than the fineness of the fibers constituting the second spunbonded nonwoven fabric. 前記筒状体の外周に巻回された外装スパンボンド不織布を更に含み、
前記外装スパンボンド不織布は、前記複合繊維からなり、かつ前記筒状体の外周に熱融着されている請求項1に記載の筒状フィルター。
It further includes an exterior spunbond nonwoven fabric wound around the outer periphery of the cylindrical body,
The cylindrical filter according to claim 1, wherein the exterior spunbonded nonwoven fabric is made of the composite fiber and is heat-sealed to the outer periphery of the cylindrical body.
前記スパンボンド不織布を構成する繊維は、ポリオレフィンを含み、
前記複合繊維は、高密度ポリエチレンを鞘成分とし、ポリプロピレンを芯成分とする芯鞘型複合繊維である請求項1に記載の筒状フィルター。
The fibers constituting the spunbond nonwoven fabric include polyolefin,
The cylindrical filter according to claim 1, wherein the composite fiber is a core-sheath type composite fiber having high-density polyethylene as a sheath component and polypropylene as a core component.
前記スパンボンド不織布を構成する繊維は、ポリオレフィンを含み、
前記複合繊維は、ポリブテン−1を鞘成分とし、ポリプロピレンを芯成分とする芯鞘型複合繊維である請求項1に記載の筒状フィルター。
The fibers constituting the spunbond nonwoven fabric include polyolefin,
2. The cylindrical filter according to claim 1, wherein the composite fiber is a core-sheath type composite fiber having polybutene-1 as a sheath component and polypropylene as a core component.
前記スパンボンド不織布を構成する繊維は、ポリエステルを含み、
前記複合繊維は、芯鞘型複合繊維であり、
前記芯鞘型複合繊維の鞘成分は、脂肪族ポリエステル及びポリエステル共重合体からなる群から選ばれる少なくとも1種であって、融点又は流動開始温度が210℃以下となる樹脂であり、
前記芯鞘型複合繊維の芯成分は、ポリエチレンテレフタレート、ポリブチレンテレフタレート及びポリトリメチレンテレフタレートからなる群から選ばれる少なくとも1種である請求項1に記載の筒状フィルター。
The fibers constituting the spunbond nonwoven fabric include polyester,
The conjugate fiber is a core-sheath type conjugate fiber,
The sheath component of the core-sheath composite fiber is at least one selected from the group consisting of aliphatic polyesters and polyester copolymers, and is a resin having a melting point or a flow start temperature of 210 ° C. or lower,
The cylindrical filter according to claim 1, wherein the core component of the core-sheath type composite fiber is at least one selected from the group consisting of polyethylene terephthalate, polybutylene terephthalate, and polytrimethylene terephthalate.
第1スパンボンド不織布と、前記第1スパンボンド不織布と重なり合う第2スパンボンド不織布とを含み、前記第1及び第2スパンボンド不織布のうち少なくとも一方は、第1熱可塑性樹脂と、前記第1熱可塑性樹脂より融点が10℃以上高い第2熱可塑性樹脂とを含む複合繊維からなり、前記第1及び第2スパンボンド不織布の熱融着温度におけるそれぞれの熱収縮率の差が5%以上有り、前記第1及び第2スパンボンド不織布をそれぞれ構成する繊維の繊度が相違する積層スパンボンド不織布を加熱することによって、各層間が熱融着された複層不織布を形成し、
前記複層不織布を、前記第1熱可塑性樹脂の融点より5℃下回る温度以上に加熱しながら巻芯に巻き取り、
巻き取られた前記複層不織布を冷却し、前記巻芯を抜き取って、前記複層不織布が巻回された筒状体を形成する筒状フィルターの製造方法。
A first spunbond nonwoven fabric and a second spunbond nonwoven fabric overlapping the first spunbond nonwoven fabric, wherein at least one of the first and second spunbond nonwoven fabrics includes a first thermoplastic resin and the first heat. A composite fiber comprising a second thermoplastic resin having a melting point higher than that of the plastic resin by 10 ° C. or more, and there is a difference of 5% or more in the respective heat shrinkage rates at the heat fusion temperature between the first and second spunbond nonwoven fabrics, By heating the laminated spunbonded nonwoven fabrics having different finenesses of the fibers constituting the first and second spunbonded nonwoven fabrics, a multilayer nonwoven fabric in which each layer is thermally fused is formed,
The multilayer nonwoven fabric is wound around a core while being heated to a temperature of 5 ° C. or lower than the melting point of the first thermoplastic resin,
The manufacturing method of the cylindrical filter which cools the wound said multilayer nonwoven fabric, extracts the said core, and forms the cylindrical body by which the said multilayer nonwoven fabric was wound.
JP2004344203A 2004-11-29 2004-11-29 Cylindrical filter and manufacturing method thereof Expired - Fee Related JP4751604B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2004344203A JP4751604B2 (en) 2004-11-29 2004-11-29 Cylindrical filter and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2004344203A JP4751604B2 (en) 2004-11-29 2004-11-29 Cylindrical filter and manufacturing method thereof

Publications (2)

Publication Number Publication Date
JP2006150222A true JP2006150222A (en) 2006-06-15
JP4751604B2 JP4751604B2 (en) 2011-08-17

Family

ID=36629133

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2004344203A Expired - Fee Related JP4751604B2 (en) 2004-11-29 2004-11-29 Cylindrical filter and manufacturing method thereof

Country Status (1)

Country Link
JP (1) JP4751604B2 (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008149737A1 (en) 2007-05-31 2008-12-11 Toray Industries, Inc. Nonwoven fabric for cylindrical bag filter, process for producing the same, and cylindrical bag filter therefrom
JP2010162522A (en) * 2009-01-19 2010-07-29 Daiwabo Holdings Co Ltd Molded filter and cylindrical filter, and method of manufacturing the same
JP2012000559A (en) * 2010-06-16 2012-01-05 Kureha Ltd Method of producing filter medium for use in microcylindrical filter
US20140248468A1 (en) * 2013-03-04 2014-09-04 Finetrack Long fiber nonwoven fabric and laminate of fabrics having long fiber nonwoven fabric
JP2017052195A (en) * 2015-09-10 2017-03-16 パナソニックIpマネジメント株式会社 Method and apparatus for producing laminate
WO2018221122A1 (en) * 2017-05-30 2018-12-06 東レ株式会社 Spunbonded nonwoven fabric for filter and method for producing same

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6017164A (en) * 1983-07-01 1985-01-29 旭化成株式会社 Nonwoven fabric
JPH0334812U (en) * 1989-08-09 1991-04-05
JPH0754256A (en) * 1993-06-07 1995-02-28 Daiwabo Create Kk Bulky nonwoven fabric
JPH08226064A (en) * 1994-12-22 1996-09-03 Chisso Corp Tubular formed article and its production
JPH11309310A (en) * 1998-02-24 1999-11-09 Chisso Corp Cylindrical molded object and filter element using the same
JP2001098453A (en) * 1999-09-28 2001-04-10 Daiwabo Co Ltd Electret nonwoven fabric and air filter
JP2001248056A (en) * 2000-02-28 2001-09-14 Unitika Ltd Composite filament nonwoven fabric and filter obtained therefrom
JP2001252510A (en) * 2000-03-10 2001-09-18 Japan Vilene Co Ltd Cylindrical filter
JP2001327817A (en) * 2000-05-19 2001-11-27 Chisso Corp Filter cartridge
JP2004041837A (en) * 2002-07-09 2004-02-12 Mitsubishi Paper Mills Ltd Deodorant-enclosed filter medium

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6017164A (en) * 1983-07-01 1985-01-29 旭化成株式会社 Nonwoven fabric
JPH0334812U (en) * 1989-08-09 1991-04-05
JPH0754256A (en) * 1993-06-07 1995-02-28 Daiwabo Create Kk Bulky nonwoven fabric
JPH08226064A (en) * 1994-12-22 1996-09-03 Chisso Corp Tubular formed article and its production
JPH11309310A (en) * 1998-02-24 1999-11-09 Chisso Corp Cylindrical molded object and filter element using the same
JP2001098453A (en) * 1999-09-28 2001-04-10 Daiwabo Co Ltd Electret nonwoven fabric and air filter
JP2001248056A (en) * 2000-02-28 2001-09-14 Unitika Ltd Composite filament nonwoven fabric and filter obtained therefrom
JP2001252510A (en) * 2000-03-10 2001-09-18 Japan Vilene Co Ltd Cylindrical filter
JP2001327817A (en) * 2000-05-19 2001-11-27 Chisso Corp Filter cartridge
JP2004041837A (en) * 2002-07-09 2004-02-12 Mitsubishi Paper Mills Ltd Deodorant-enclosed filter medium

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008149737A1 (en) 2007-05-31 2008-12-11 Toray Industries, Inc. Nonwoven fabric for cylindrical bag filter, process for producing the same, and cylindrical bag filter therefrom
JP2010162522A (en) * 2009-01-19 2010-07-29 Daiwabo Holdings Co Ltd Molded filter and cylindrical filter, and method of manufacturing the same
JP2012000559A (en) * 2010-06-16 2012-01-05 Kureha Ltd Method of producing filter medium for use in microcylindrical filter
KR101576843B1 (en) 2013-03-04 2015-12-11 파인트랙 Long fiber nonwoven fabric and laminate of fabrics having long fiber nonwoven fabric
CN104032534A (en) * 2013-03-04 2014-09-10 法恩翠克股份有限公司 Long fiber nonwoven fabric and laminate of fabrics having long fiber nonwoven fabric
JP2014196585A (en) * 2013-03-04 2014-10-16 株式会社finetrack Filament nonwoven fabric and laminated fabric comprising the filament nonwoven fabric
US20140248468A1 (en) * 2013-03-04 2014-09-04 Finetrack Long fiber nonwoven fabric and laminate of fabrics having long fiber nonwoven fabric
CN106192279A (en) * 2013-03-04 2016-12-07 法恩翠克股份有限公司 Nonwoven fabric of long fibers and there is the lamination cloth of this nonwoven fabric of long fibers
US10005255B2 (en) 2013-03-04 2018-06-26 Finetrack Long fiber nonwoven fabric and laminate of fabrics having long fiber nonwoven fabric
JP2017052195A (en) * 2015-09-10 2017-03-16 パナソニックIpマネジメント株式会社 Method and apparatus for producing laminate
WO2018221122A1 (en) * 2017-05-30 2018-12-06 東レ株式会社 Spunbonded nonwoven fabric for filter and method for producing same
JPWO2018221122A1 (en) * 2017-05-30 2020-03-26 東レ株式会社 Spunbonded nonwoven fabric for filter and method for producing the same
JP7180376B2 (en) 2017-05-30 2022-11-30 東レ株式会社 METHOD FOR MANUFACTURING SPUNBOND NONWOVEN FABRIC FOR FILTER

Also Published As

Publication number Publication date
JP4751604B2 (en) 2011-08-17

Similar Documents

Publication Publication Date Title
JP6593170B2 (en) Fiber laminate including ultrafine fibers and filter comprising the same
US20200216979A1 (en) Multi-die melt blowing system for forming co-mingled structures and method thereof
WO1998013123A1 (en) High-precision filter
JP5823205B2 (en) Cartridge filter
WO2007040104A1 (en) Nonwoven fabric for filters
CN108472566B (en) Cartridge filter using nanofiber composite fiber yarn and method for manufacturing the same
JPH1190135A (en) Pleated filter
JP4800643B2 (en) Cylindrical filter and manufacturing method thereof
JP4751604B2 (en) Cylindrical filter and manufacturing method thereof
JP2007152216A (en) Nonwoven fabric for filter
KR100367542B1 (en) Cylindrical molded article and its manufacturing method
WO2014148504A1 (en) Aggregate-removing filter material, aggregate removal method, white blood cell-removing filter, and blood product filtering method
JPH0596110A (en) Cylindrical filter and its production
JP4139141B2 (en) Cylindrical filter and manufacturing method thereof
JP5836191B2 (en) Cylindrical filter
JPH08226064A (en) Tubular formed article and its production
JP5836190B2 (en) Cylindrical filter
JP3131217B2 (en) Cylindrical filter for microfiltration
JP4914569B2 (en) Cylindrical filter and manufacturing method thereof
JP4604351B2 (en) Filter cartridge
JPH04145914A (en) Cartridge filter
JP2001096110A (en) Cylindrical filter
JP2000271417A (en) Filter medium sheet and pleat filter using the same
JP2005238098A (en) Filter medium for air filter and its production method
JPH08209519A (en) Cylindrical formed body and its production or the like

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20071030

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20100326

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20100406

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20100604

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20110517

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20110523

R150 Certificate of patent or registration of utility model

Ref document number: 4751604

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20140527

Year of fee payment: 3

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

S111 Request for change of ownership or part of ownership

Free format text: JAPANESE INTERMEDIATE CODE: R313115

S111 Request for change of ownership or part of ownership

Free format text: JAPANESE INTERMEDIATE CODE: R313115

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

LAPS Cancellation because of no payment of annual fees