JP2019210567A - Wet laid non-woven fabric - Google Patents
Wet laid non-woven fabric Download PDFInfo
- Publication number
- JP2019210567A JP2019210567A JP2018106853A JP2018106853A JP2019210567A JP 2019210567 A JP2019210567 A JP 2019210567A JP 2018106853 A JP2018106853 A JP 2018106853A JP 2018106853 A JP2018106853 A JP 2018106853A JP 2019210567 A JP2019210567 A JP 2019210567A
- Authority
- JP
- Japan
- Prior art keywords
- nonwoven fabric
- fiber
- wet nonwoven
- range
- polyester
- 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
Links
- 239000004745 nonwoven fabric Substances 0.000 title claims abstract description 95
- 239000000835 fiber Substances 0.000 claims abstract description 151
- 239000011230 binding agent Substances 0.000 claims abstract description 68
- 229920000728 polyester Polymers 0.000 claims abstract description 51
- 238000002425 crystallisation Methods 0.000 claims abstract description 28
- 230000008025 crystallization Effects 0.000 claims abstract description 28
- -1 polyethylene terephthalate Polymers 0.000 claims abstract description 21
- 239000011148 porous material Substances 0.000 claims abstract description 21
- 230000035699 permeability Effects 0.000 claims abstract description 20
- 238000010438 heat treatment Methods 0.000 claims abstract description 15
- 229920001225 polyester resin Polymers 0.000 claims abstract description 13
- 239000004645 polyester resin Substances 0.000 claims abstract description 8
- 229920000139 polyethylene terephthalate Polymers 0.000 claims abstract description 6
- 239000005020 polyethylene terephthalate Substances 0.000 claims abstract description 6
- 229920005989 resin Polymers 0.000 claims abstract description 3
- 239000011347 resin Substances 0.000 claims abstract description 3
- 229920006240 drawn fiber Polymers 0.000 abstract description 16
- 238000000034 method Methods 0.000 description 22
- 239000000123 paper Substances 0.000 description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 13
- 238000003490 calendering Methods 0.000 description 7
- 238000001035 drying Methods 0.000 description 6
- 230000000704 physical effect Effects 0.000 description 6
- 238000007796 conventional method Methods 0.000 description 5
- 230000007423 decrease Effects 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 238000002156 mixing Methods 0.000 description 5
- 238000011282 treatment Methods 0.000 description 5
- 238000009987 spinning Methods 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 description 3
- 239000002270 dispersing agent Substances 0.000 description 3
- 230000001771 impaired effect Effects 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 238000002074 melt spinning Methods 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 239000011087 paperboard Substances 0.000 description 3
- 239000002002 slurry Substances 0.000 description 3
- 238000010998 test method Methods 0.000 description 3
- 239000004698 Polyethylene Substances 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- WNLRTRBMVRJNCN-UHFFFAOYSA-N adipic acid Chemical compound OC(=O)CCCCC(O)=O WNLRTRBMVRJNCN-UHFFFAOYSA-N 0.000 description 2
- QMKYBPDZANOJGF-UHFFFAOYSA-N benzene-1,3,5-tricarboxylic acid Chemical compound OC(=O)C1=CC(C(O)=O)=CC(C(O)=O)=C1 QMKYBPDZANOJGF-UHFFFAOYSA-N 0.000 description 2
- WERYXYBDKMZEQL-UHFFFAOYSA-N butane-1,4-diol Chemical compound OCCCCO WERYXYBDKMZEQL-UHFFFAOYSA-N 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000011156 evaluation Methods 0.000 description 2
- 238000007731 hot pressing Methods 0.000 description 2
- QQVIHTHCMHWDBS-UHFFFAOYSA-N isophthalic acid Chemical compound OC(=O)C1=CC=CC(C(O)=O)=C1 QQVIHTHCMHWDBS-UHFFFAOYSA-N 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- XNGIFLGASWRNHJ-UHFFFAOYSA-N phthalic acid Chemical compound OC(=O)C1=CC=CC=C1C(O)=O XNGIFLGASWRNHJ-UHFFFAOYSA-N 0.000 description 2
- 229920000573 polyethylene Polymers 0.000 description 2
- 238000006116 polymerization reaction Methods 0.000 description 2
- CXMXRPHRNRROMY-UHFFFAOYSA-N sebacic acid Chemical compound OC(=O)CCCCCCCCC(O)=O CXMXRPHRNRROMY-UHFFFAOYSA-N 0.000 description 2
- 239000004094 surface-active agent Substances 0.000 description 2
- ARCGXLSVLAOJQL-UHFFFAOYSA-N trimellitic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C(C(O)=O)=C1 ARCGXLSVLAOJQL-UHFFFAOYSA-N 0.000 description 2
- DNIAPMSPPWPWGF-VKHMYHEASA-N (+)-propylene glycol Chemical compound C[C@H](O)CO DNIAPMSPPWPWGF-VKHMYHEASA-N 0.000 description 1
- YPFDHNVEDLHUCE-UHFFFAOYSA-N 1,3-propanediol Substances OCCCO YPFDHNVEDLHUCE-UHFFFAOYSA-N 0.000 description 1
- PXGZQGDTEZPERC-UHFFFAOYSA-N 1,4-cyclohexanedicarboxylic acid Chemical compound OC(=O)C1CCC(C(O)=O)CC1 PXGZQGDTEZPERC-UHFFFAOYSA-N 0.000 description 1
- SHSGDXCJYVZFTP-UHFFFAOYSA-N 4-ethoxybenzoic acid Chemical compound CCOC1=CC=C(C(O)=O)C=C1 SHSGDXCJYVZFTP-UHFFFAOYSA-N 0.000 description 1
- 229920001283 Polyalkylene terephthalate Polymers 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- ZJCCRDAZUWHFQH-UHFFFAOYSA-N Trimethylolpropane Chemical compound CCC(CO)(CO)CO ZJCCRDAZUWHFQH-UHFFFAOYSA-N 0.000 description 1
- YIMQCDZDWXUDCA-UHFFFAOYSA-N [4-(hydroxymethyl)cyclohexyl]methanol Chemical compound OCC1CCC(CO)CC1 YIMQCDZDWXUDCA-UHFFFAOYSA-N 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000013543 active substance Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- WNLRTRBMVRJNCN-UHFFFAOYSA-L adipate(2-) Chemical compound [O-]C(=O)CCCCC([O-])=O WNLRTRBMVRJNCN-UHFFFAOYSA-L 0.000 description 1
- 235000011037 adipic acid Nutrition 0.000 description 1
- 239000001361 adipic acid Substances 0.000 description 1
- 150000007933 aliphatic carboxylic acids Chemical class 0.000 description 1
- 239000003242 anti bacterial agent Substances 0.000 description 1
- 239000002518 antifoaming agent Substances 0.000 description 1
- 239000002519 antifouling agent Substances 0.000 description 1
- 150000001732 carboxylic acid derivatives Chemical class 0.000 description 1
- 239000000306 component Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000002781 deodorant agent Substances 0.000 description 1
- 150000002009 diols Chemical class 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000003063 flame retardant Substances 0.000 description 1
- 239000006081 fluorescent whitening agent Substances 0.000 description 1
- 230000009477 glass transition Effects 0.000 description 1
- XXMIOPMDWAUFGU-UHFFFAOYSA-N hexane-1,6-diol Chemical compound OCCCCCCO XXMIOPMDWAUFGU-UHFFFAOYSA-N 0.000 description 1
- 239000012510 hollow fiber Substances 0.000 description 1
- 239000012770 industrial material Substances 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000006224 matting agent Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 125000005487 naphthalate group Chemical group 0.000 description 1
- RXOHFPCZGPKIRD-UHFFFAOYSA-N naphthalene-2,6-dicarboxylic acid Chemical compound C1=C(C(O)=O)C=CC2=CC(C(=O)O)=CC=C21 RXOHFPCZGPKIRD-UHFFFAOYSA-N 0.000 description 1
- SLCVBVWXLSEKPL-UHFFFAOYSA-N neopentyl glycol Chemical compound OCC(C)(C)CO SLCVBVWXLSEKPL-UHFFFAOYSA-N 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- WXZMFSXDPGVJKK-UHFFFAOYSA-N pentaerythritol Chemical compound OCC(CO)(CO)CO WXZMFSXDPGVJKK-UHFFFAOYSA-N 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 229920003207 poly(ethylene-2,6-naphthalate) Polymers 0.000 description 1
- 229920000747 poly(lactic acid) Polymers 0.000 description 1
- 229920001281 polyalkylene Polymers 0.000 description 1
- 229920001515 polyalkylene glycol Polymers 0.000 description 1
- 229920002961 polybutylene succinate Polymers 0.000 description 1
- 239000004631 polybutylene succinate Substances 0.000 description 1
- 229920001707 polybutylene terephthalate Polymers 0.000 description 1
- 239000011112 polyethylene naphthalate Substances 0.000 description 1
- 239000004626 polylactic acid Substances 0.000 description 1
- 229920000166 polytrimethylene carbonate Polymers 0.000 description 1
- 229920002215 polytrimethylene terephthalate Polymers 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- KKEYFWRCBNTPAC-UHFFFAOYSA-L terephthalate(2-) Chemical compound [O-]C(=O)C1=CC=C(C([O-])=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-L 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Abstract
Description
本発明は湿式不織布に関し、さらに詳しくは均一性に優れた高通気性の湿式不織布に関する。 The present invention relates to a wet nonwoven fabric, and more particularly to a highly breathable wet nonwoven fabric excellent in uniformity.
ポリエステル系バインダー繊維を原料の一部に使用した抄紙法による湿式不織布は、近年になって優れた物性及びコスト優位性の面から、広く使用されてきている。特に低目付の湿式不織布においては顕著であって、従来から抄紙用バインダー繊維として用いられてきたポリエチレン繊維、ポリビニルアルコール繊維等に比較して、機械的特性、電気的特性、耐熱性、寸法安定性、疎水性等の物性において、ポリエステル繊維に優位性がある。 In recent years, wet nonwoven fabrics by a papermaking method using polyester binder fibers as a part of raw materials have been widely used from the viewpoint of excellent physical properties and cost advantages. It is particularly noticeable in low-weight wet nonwoven fabrics, compared to polyethylene fibers, polyvinyl alcohol fibers, etc. that have been used as papermaking binder fibers in the past, mechanical properties, electrical properties, heat resistance, dimensional stability. In terms of physical properties such as hydrophobicity, polyester fibers are superior.
そのような従来技術としては、例えば特許文献１では、単繊維繊度が１．５ｄｔｅｘ以下であり、乾燥時の熱収縮が小さく接着性に優れたポリエステルバインダー繊維が提案されている。また、特許文献２では、より接着力の高いバインダー繊維として、単繊維繊度が１０ｄｔｅｘ以下のポリエステル系未延伸バインダー繊維が提案されている。特許文献３では、繊維形成成分と熱接着性成分からなるポリエステル系複合繊維を用いた、目付が５〜１００ｇ／ｍ２の剛性の高いポリエステル不織布が提案されている。 As such a conventional technique, for example, Patent Document 1 proposes a polyester binder fiber having a single fiber fineness of 1.5 dtex or less, a small thermal shrinkage during drying, and excellent adhesiveness. Patent Document 2 proposes a polyester-based unstretched binder fiber having a single fiber fineness of 10 dtex or less as a binder fiber having higher adhesive strength. Patent Document 3 proposes a highly rigid polyester nonwoven fabric having a basis weight of 5 to 100 g / m 2 using a polyester-based composite fiber composed of a fiber-forming component and a thermal adhesive component.
しかしこのような低目付の湿式不織布においては、熱カレンダー加工の際にバインダーがフィルム化し、通気度が低下するという問題があった。特に、フィルターやセパレータなどの用途においては、通気度を維持することが重要であり、また緻密かつ均一な通気度の湿式不織布が求められていた。 However, such a low-wet wet nonwoven fabric has a problem that the binder becomes a film during thermal calendering and the air permeability decreases. In particular, in applications such as filters and separators, it is important to maintain air permeability, and a wet nonwoven fabric having a dense and uniform air permeability has been demanded.
本発明は、上記背景のもとになされたものであり、高通気度でありながら緻密かつ均一性に優れた湿式不織布を提供することにある。 The present invention has been made based on the above background, and it is an object of the present invention to provide a wet nonwoven fabric that is dense and excellent in uniformity while having high air permeability.
本発明の湿式不織布は、主にポリエステル系樹脂から構成されるポリエステル系の延伸繊維とバインダー繊維とからなる湿式不織布であって、カレンダー熱処理前のバインダー繊維の単繊維繊度が０．２ｄｔｅｘ未満であり、カレンダー熱処理後にバインダー繊維が接着していることを特徴とする。
さらには、湿式不織布を構成する繊維の繊維長が２０ｍｍ以下であること、バインダー繊維の結晶化温度が８０〜１５０℃の範囲であることが好ましく、またポリエステル系樹脂がポリエチレンテレフタレート樹脂であることや、バインダー繊維の含有率が５重量％以上であることが好ましい。
また、不織布の厚さが２０μｍ以下であることや貫通孔の平均孔径が０．１〜５．０μｍの範囲内であること、さらには湿式不織布の目付が１〜３０ｇ／ｍ２の範囲であり、通気度が１．８〜３６ｃｍ３／（ｃｍ２・ｓｅｃ）の範囲内であることが好ましい。
The wet nonwoven fabric of the present invention is a wet nonwoven fabric mainly composed of polyester-based drawn fibers and binder fibers mainly composed of a polyester resin, and the single fiber fineness of the binder fibers before calender heat treatment is less than 0.2 dtex. The binder fiber is adhered after the calender heat treatment.
Furthermore, the fiber length of the fibers constituting the wet nonwoven fabric is preferably 20 mm or less, the crystallization temperature of the binder fiber is preferably in the range of 80 to 150 ° C., and the polyester resin is a polyethylene terephthalate resin. The binder fiber content is preferably 5% by weight or more.
Moreover, the thickness of the nonwoven fabric is 20 μm or less, the average pore diameter of the through holes is in the range of 0.1 to 5.0 μm, and the basis weight of the wet nonwoven fabric is in the range of 1 to 30 g / m 2 . The air permeability is preferably in the range of 1.8 to 36 cm 3 / (cm 2 · sec).
本発明によれば、高通気度でありながら緻密かつ均一性に優れた湿式不織布が提供される。 ADVANTAGE OF THE INVENTION According to this invention, the wet nonwoven fabric excellent in the density and the uniformity was provided, although it is high air permeability.
本発明の湿式不織布は、主にポリエステル系樹脂から構成されるポリエステル系の延伸繊維とバインダー繊維とからなる湿式不織布である。そして、カレンダー熱処理前のバインダー繊維の単繊維繊度が０．２ｄｔｅｘ未満であり、カレンダー工程の加圧、加熱処理によって、バインダー繊維が接着していることを必須とする。 The wet nonwoven fabric of the present invention is a wet nonwoven fabric composed of polyester-based drawn fibers and binder fibers mainly composed of a polyester-based resin. And it is essential that the single fiber fineness of the binder fiber before calendar heat treatment is less than 0.2 dtex, and that the binder fiber is adhered by the pressurization and heat treatment of the calendar process.
このような本発明に用いるポリエステル系樹脂としては、ポリエチレンテレフタレートやポリトリメ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アルキレンテレフタレートやポリエチレンナフタレート等のポリアルキレンナフタレートといった芳香族ジカルボン酸と脂肪族ジオールのポリエステル、ポリアルキレンシクロヘキサンジカルボキシレート等の脂環族カルボン酸と脂肪族ジオールのポリエステル、ポリシクロヘキサンジメタノールテレフタレート等の芳香族カルボン酸と脂環族ジオールのポリエステル、ポリエチレンサクシネートやポリブチレンサクシネート、ポリエチレンアジペート等の脂肪族カルボン酸と脂肪族ジオールのポリエステル、ポリ乳酸やポリヒドロキシ安息香酸等のポリヒドロキシカルボン酸、等が例示される。また、目的に応じて、酸成分としてイソフタル酸、フタル酸、アジピン酸、セバシン酸、α、β―（４−カルボキシフェノキシ）エタン、４、４−ジカルボキシフェニル、５−ナトリウムスルホイソフタル酸、２，６−ナフタレンジカルボン酸、１、４−シクロヘキサンジカルボン酸またはこれらのエステル類、ジオール成分としてジエチレングリコール、１、３−プロパンジオール、１，４−ブタンジオール、１，６−ヘキサンジオール、ネオペンチルグリコール、１，４−シクロヘキサンジメタノール、ポリアルキレングリコール、等を１成分以上共重合させてもよく、さらにペンタエリスリトール、トリメチロールプロパン、トリメリット酸、トリメシン酸等の３個以上のカルボン酸成分または水酸基をもつ成分を共重合して分岐をもたせてもよい。また、上記に例示されるような組成の異なるポリエステルの混合物も含まれる。なお、これらのポリエステルには、公知の添加剤、例えば、顔料、染料、艶消し剤、防汚剤、抗菌剤、消臭剤、蛍光増白剤、難燃剤、安定剤、紫外線吸収剤、滑剤等を含んでもよい。 Polyester resins used in the present invention include polyesters of aromatic dicarboxylic acids and aliphatic diols such as polyalkylene terephthalates such as polyethylene terephthalate, polytrimethylene terephthalate, and polybutylene terephthalate, and polyalkylene naphthalates such as polyethylene naphthalate. Polyesters of alicyclic carboxylic acids and aliphatic diols such as polyalkylenecyclohexanedicarboxylate, polyesters of aromatic carboxylic acids and alicyclic diols such as polycyclohexanedimethanol terephthalate, polyethylene succinate and polybutylene succinate, polyethylene Polyesters of aliphatic carboxylic acids such as adipate and aliphatic diols, polyhydroxycarboxylic acids such as polylactic acid and polyhydroxybenzoic acid, There are exemplified. Depending on the purpose, isophthalic acid, phthalic acid, adipic acid, sebacic acid, α, β- (4-carboxyphenoxy) ethane, 4,4-dicarboxyphenyl, 5-sodium sulfoisophthalic acid, 2 , 6-Naphthalenedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid or esters thereof, diethylene glycol as a diol component, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, One or more components such as 1,4-cyclohexanedimethanol, polyalkylene glycol and the like may be copolymerized, and further, three or more carboxylic acid components such as pentaerythritol, trimethylolpropane, trimellitic acid, trimesic acid, etc. Branched by copolymerizing components It may be allowed. Also included are mixtures of polyesters having different compositions as exemplified above. These polyesters include known additives such as pigments, dyes, matting agents, antifouling agents, antibacterial agents, deodorants, fluorescent whitening agents, flame retardants, stabilizers, ultraviolet absorbers, and lubricants. Etc. may be included.
またポリエステル繊維の形状としては、断面外周が丸断面であることが好ましく、中実繊維のみならず中空繊維でることも好ましい。また繊維断面形状が丸断面以外の、楕円断面、３〜８葉断面等の多葉断面、３〜８角の多角形断面などの各種異型断面であることも好ましい。 Moreover, as a shape of a polyester fiber, it is preferable that a cross-sectional outer periphery is a round cross section, and it is also preferable that it is not only a solid fiber but a hollow fiber. It is also preferable that the fiber cross-sectional shape is an elliptical cross-section other than a round cross-section, a multi-leaf cross-section such as a 3-8 leaf cross-section, and various irregular cross-sections such as a 3-8 octagonal cross-section.
さて本発明の湿式不織布では、繊維として、主にポリエステル系樹脂から構成されるポリエステル系の延伸繊維と、同じく主にポリエステル系樹脂から構成されるバインダー繊維とからなるものである。さらに必要に応じ、その他の繊維を含んでも良い。 Now, in the wet nonwoven fabric of the present invention, the fibers are composed of polyester stretched fibers mainly composed of a polyester-based resin and binder fibers composed mainly of a polyester-based resin. Further, if necessary, other fibers may be included.
そして本発明にて用いられる細繊度のポリエステル系のバインダー繊維としては、フロー延伸した繊維であることが好ましい。 The fine polyester-based binder fiber used in the present invention is preferably a flow-stretched fiber.
より具体的には例えば、まずポリエステル樹脂からなるペレットを常法で乾燥し、スクリュー式押出機を装備した溶融紡糸装置にて溶融し、常法で紡糸し、引き取り、未延伸ポリエステル繊維を得る。そしてその未延伸ポリエステル繊維をフロー延伸することによって、バインダー繊維が得られる。 More specifically, for example, first, pellets made of polyester resin are dried by a conventional method, melted by a melt spinning apparatus equipped with a screw type extruder, spun by a conventional method, and taken to obtain unstretched polyester fibers. And a binder fiber is obtained by carrying out flow drawing of the unstretched polyester fiber.
ここでフロー延伸とは、ポリエステルをそのガラス転移温度（以下、Ｔｇと記す）より高い温度で延伸する、フロー延伸現象を利用する延伸方法をいう。このようなフロー延伸では、高い倍率での延伸が可能であるため、本発明では単繊維繊度が細い未延伸繊維を得ることが可能となった。さらに、より安定したフロー延伸を起こさせるためには、使用するポリエステルのＴｇよりも１０℃以上高い媒体中でフロー延伸することが望ましい。また、媒体としては水や水蒸気を用いることが好ましく、特には８０〜１１０℃の湿熱中で延伸することが好ましい。より具体的には８０℃以上１００℃未満の温水中や、１１０℃未満の水蒸気中にて行うことが好ましい。 Here, the flow stretching refers to a stretching method using a flow stretching phenomenon in which polyester is stretched at a temperature higher than its glass transition temperature (hereinafter referred to as Tg). In such flow drawing, since drawing at a high magnification is possible, in the present invention, it is possible to obtain undrawn fibers having a fine single fiber fineness. Furthermore, in order to cause more stable flow stretching, it is desirable to perform flow stretching in a medium higher by 10 ° C. or more than the Tg of the polyester used. Moreover, it is preferable to use water or water vapor as the medium, and it is particularly preferable to stretch in a wet heat of 80 to 110 ° C. More specifically, it is preferable to carry out in warm water at 80 ° C. or higher and lower than 100 ° C. or in water vapor at 110 ° C.
またバインダーとなるポリエステル繊維を得るためのフロー延伸倍率としては、５．０倍以上、さらに好ましくは１０倍以上、さらには１５〜１４０倍、特には２０〜９０倍の範囲とすることが好ましい。このような条件にて高倍率延伸を行うことで、通常の延伸方法では得難い、細繊度のバインダー繊維を得ることが容易となる。 Moreover, as a flow draw ratio for obtaining the polyester fiber used as a binder, it is preferable to set it as the range of 5.0 times or more, More preferably, 10 times or more, Furthermore, 15-140 times, Especially 20-90 times. By performing high-magnification stretching under such conditions, it becomes easy to obtain a binder fiber having a fineness that is difficult to obtain by a normal stretching method.
また、フロー延伸に際しては、繊維同士の膠着が起こり易いため、繊維表面に膠着防止効果のある活性剤等を存在させることが好ましい。 In addition, during flow drawing, the fibers tend to stick together, so it is preferable that an active agent or the like having an anti-sticking effect be present on the fiber surface.
そしてこのフロー延伸されたポリエステル繊維は、未延伸繊維に近い物性であるため、フロー延伸に引き続いてわずかにネック延伸を行い、さらに細いポリエステルバインダー繊維とすることも好ましい。なお、このネック延伸もフロー延伸と同様に媒体中にて行うことが好ましく、特には６０〜８０℃の温水中で行うことが好ましい。また、このようなバインダー繊維は必要に応じて、所定の機能を有する界面活性剤の付与、捲縮の付与、所定のカット長での切断等の処理を実施することが好ましい。 Since the flow-stretched polyester fiber has physical properties close to those of the unstretched fiber, it is also preferable that the neck fiber is slightly stretched after the flow stretching to form a finer polyester binder fiber. In addition, it is preferable to perform this neck extending | stretching in a medium similarly to flow extending | stretching, and it is preferable to carry out in 60-80 degreeC warm water especially. Further, such binder fibers are preferably subjected to treatments such as application of a surfactant having a predetermined function, application of crimp, and cutting with a predetermined cut length as necessary.
また本発明において用いられるバインダー繊維としては、上述したようにフロー延伸されたポリエステル繊維を用いることが好ましく、特にはバインダー繊維が示差熱測定において結晶化温度を有していることが好ましい。ここで結晶化温度とは、示差熱分析装置で測定した昇温時結晶化ピークの頂点の温度である。一般に延伸を施したポリエステル繊維は配向結晶化が進行し、結晶化ピークを示さないが、Ｔｇより高温の媒体中で延伸を施した、いわゆるフロー延伸を行ったようなポリエステル繊維では、配向結晶化を抑制しながら伸長させるため、結晶化温度を示す。このような結晶化温度を有するポリエステル繊維は、加熱される過程において接着性を発現し、延伸ポリエステル繊維等の他の繊維やお互い同士で接合して繊維構造体を与えるため、バインダー繊維として特に有効である。なお十分に延伸、特に十分にネック延伸したポリエステル繊維は結晶化温度を有さず、バインダー繊維としては機能しない。 Further, as the binder fiber used in the present invention, it is preferable to use the polyester fiber that has been flow-drawn as described above, and it is particularly preferable that the binder fiber has a crystallization temperature in the differential heat measurement. Here, the crystallization temperature is the temperature at the top of the crystallization peak at the time of temperature rise measured by a differential thermal analyzer. In general, stretched polyester fibers undergo oriented crystallization and do not show a crystallization peak. However, oriented polyester crystals that have been stretched in a medium having a temperature higher than Tg, such as those subjected to flow stretching, are oriented crystallization. In order to elongate while suppressing the crystallization temperature, the crystallization temperature is shown. Polyester fibers having such a crystallization temperature exhibit adhesiveness in the process of being heated, and are particularly effective as binder fibers because they provide a fiber structure by bonding with other fibers such as drawn polyester fibers and each other. It is. Polyester fibers that are sufficiently stretched, particularly sufficiently neck-stretched, do not have a crystallization temperature and do not function as binder fibers.
バインダー繊維の結晶化温度は、８０〜１５０℃の範囲内であることが好ましく、さらには９０〜１３０℃、特には１００〜１２０℃の範囲であることが好ましい。 The crystallization temperature of the binder fiber is preferably in the range of 80 to 150 ° C, more preferably 90 to 130 ° C, particularly preferably 100 to 120 ° C.
本発明の湿式不織布では、好ましいバインダー繊維としては低い結晶化温度を持つ繊維をバインダー繊維として用いることが好ましい。この場合、その湿式不織布の製造工程の中でかかる熱によって結晶化が進み、カレンダー等の熱プレス工程の際においても、フィルム化しにくい、という効果が発現する。すると、本発明においては、バインダー繊維の混抄率を上げても、通気性を維持した湿式不織布を製造することが可能となる。 In the wet nonwoven fabric of the present invention, it is preferable to use a fiber having a low crystallization temperature as a binder fiber as a preferable binder fiber. In this case, crystallization proceeds due to heat applied in the manufacturing process of the wet nonwoven fabric, and an effect that it is difficult to form a film is exhibited even in a hot pressing process such as a calendar. Then, in this invention, even if it raises the mixing ratio of a binder fiber, it becomes possible to manufacture the wet nonwoven fabric which maintained air permeability.
ただしこの結晶化温度が低すぎる場合には、特に７０℃近辺の場合、ポリエステル延伸繊維のＴｇに近い温度で結晶化が進むことになり、バインダーとして好ましくない傾向にある。また、逆に結晶化温度が高すぎる場合、接着するために高温を要しコストが増加する傾向にある。 However, when this crystallization temperature is too low, especially in the vicinity of 70 ° C., crystallization proceeds at a temperature close to Tg of the stretched polyester fiber, which tends to be undesirable as a binder. On the other hand, if the crystallization temperature is too high, a high temperature is required for bonding, and the cost tends to increase.
このようなバインダー繊維における結晶化温度の調整は、チップ粘度（固有粘度）、単繊維繊度、紡糸条件を変更することにより可能である。例えば、チップ粘度を下げる、重合度を下げる、紡糸時の工程温度を上げる、または単繊維繊度を大きくするなどの手段によって、結晶化温度を上げることができる。逆に、チップ粘度を上げる、重合度を上げる、紡糸時の工程温度を下げる、単繊維繊度を小さくするなどの手段によって、結晶化温度を下げることができる。 Adjustment of the crystallization temperature in such a binder fiber is possible by changing chip viscosity (intrinsic viscosity), single fiber fineness, and spinning conditions. For example, the crystallization temperature can be raised by means such as lowering the chip viscosity, lowering the degree of polymerization, raising the process temperature during spinning, or increasing the single fiber fineness. Conversely, the crystallization temperature can be lowered by means such as increasing the chip viscosity, increasing the degree of polymerization, decreasing the process temperature during spinning, or decreasing the single fiber fineness.
そして本発明の不織布においては、不織布を構成するバインダー繊維の単繊維繊度が０．２ｄｔｅｘ未満であり、バインダー繊維が熱カレンダー処理によって接着している。バインダー繊維の繊度としては、０．２ｄｔｅｘ未満、さらには０．０２〜０．１５ｄｔｅｘ、特には０．０６〜０．１０ｄｔｅｘの範囲内にあることが好ましい。バインダー繊維の繊度が大きすぎる場合、繊維１本あたりの重量が高いため、特に低目付の湿式不織布を目的とする場合、不織布を構成する繊維の本数が極端に少なくなり、その結果、バインダー繊維としての接着点が減少し、均一な不織布を製造することが困難になる。また、ピンホールが発生し地合いが低下するなどの問題も生じやすい傾向にある。 And in the nonwoven fabric of this invention, the single fiber fineness of the binder fiber which comprises a nonwoven fabric is less than 0.2 dtex, and the binder fiber has adhere | attached by the heat calendar process. The fineness of the binder fiber is preferably less than 0.2 dtex, more preferably 0.02 to 0.15 dtex, particularly preferably 0.06 to 0.10 dtex. When the fineness of the binder fiber is too large, the weight per fiber is high, and particularly when a wet nonwoven fabric with a low basis weight is intended, the number of fibers constituting the nonwoven fabric is extremely reduced. The adhesion point of the sheet decreases, and it becomes difficult to produce a uniform nonwoven fabric. There is also a tendency for problems such as pinholes to occur and a decrease in texture.
本発明の湿式不織布はポリエステル系のバインダー繊維と延伸繊維を含有するものであるが、バインダー繊維とともに用いる延伸繊維としては、以下のような延伸繊維を主体繊維として含有することが好ましい。なお延伸繊維としては、通常の延伸を行った繊維であっても良いが、さらには、上記のようなフロー延伸した後に、さらに十分にネック延伸を行い、結晶化温度を示さないポリエステル延伸繊維であることが好ましい。 The wet nonwoven fabric of the present invention contains a polyester-based binder fiber and a drawn fiber, and the drawn fiber used together with the binder fiber preferably contains the following drawn fiber as a main fiber. The drawn fiber may be a fiber that has been subjected to normal drawing, but further, it is a polyester drawn fiber that does not exhibit a crystallization temperature by performing neck stretching sufficiently after the flow drawing as described above. Preferably there is.
主体繊維ともなる延伸繊維としては、単繊維繊度は１．０ｄｔｅｘ以下であることが好ましく、より好ましくは０．００５〜０．１ｄｔｅｘの範囲内、さらに好ましくは０．０１〜０．０５ｄｔｅｘの範囲である。延伸繊維を得るためのネック延伸倍率としては、１．５〜４倍の範囲であることが好ましく、特には２．０〜３．５倍の範囲であることが好ましい。バインダー繊維と同じく、この延伸繊維もフロー延伸と同様に媒体中にて行うことが好ましく、特には６０〜８０℃の温水中で行うことが好ましい。 The drawn fiber that is also the main fiber preferably has a single fiber fineness of 1.0 dtex or less, more preferably in the range of 0.005 to 0.1 dtex, and still more preferably in the range of 0.01 to 0.05 dtex. is there. The neck draw ratio for obtaining drawn fibers is preferably in the range of 1.5 to 4 times, and more preferably in the range of 2.0 to 3.5 times. Similar to the binder fiber, this stretched fiber is preferably carried out in a medium as in the case of the flow drawing, particularly preferably in hot water of 60 to 80 ° C.
さらに本発明に用いられる延伸繊維はネック延伸後、繊維の収縮特性を調節するために各種熱処理を行うことも好ましい。熱処理方法は特に限定されず、緊張熱処理、制限収縮処理、緩和熱処理等、いずれの熱処理も施すことができる。また、延伸処理後のポリエステル繊維は必要に応じて、所定の機能を有する界面活性剤の付与、捲縮の付与、所定のカット長での切断等の処理を実施することが好ましい。 Furthermore, the drawn fiber used in the present invention is preferably subjected to various heat treatments after neck neck drawing in order to adjust the shrinkage characteristics of the fiber. The heat treatment method is not particularly limited, and any heat treatment such as tension heat treatment, limited shrinkage treatment, or relaxation heat treatment can be performed. Moreover, it is preferable that the polyester fiber after the drawing treatment is subjected to a treatment such as application of a surfactant having a predetermined function, application of crimp, cutting with a predetermined cut length, as necessary.
そしてこのような本発明の湿式不織布に好適に用いられる繊維としては、その繊維長が２０ｍｍ以下であることが好ましい。特には湿式不織布を構成する繊維が、ポリエステル系樹脂からなるバインダー繊維および延伸繊維であって、その繊維長が共に２０ｍｍ以下であることが好ましい。さらにはその繊維長が、より好ましくは０．５〜５ｍｍ、特には１〜３ｍｍの範囲であることが好ましい。本発明の湿式不織布を製造する場合において、繊維長が長すぎると、特に各繊維を水中にて分散させる際に繊維が絡み合って、その部分が紙の欠点となり、均一な湿式不織布（紙）を得にくい傾向にある。 And as a fiber used suitably for such a wet nonwoven fabric of this invention, it is preferable that the fiber length is 20 mm or less. In particular, it is preferable that the fibers constituting the wet nonwoven fabric are binder fibers and drawn fibers made of a polyester-based resin, and both the fiber lengths are 20 mm or less. Further, the fiber length is more preferably in the range of 0.5 to 5 mm, particularly 1 to 3 mm. In the case of producing the wet nonwoven fabric of the present invention, if the fiber length is too long, particularly when each fiber is dispersed in water, the fibers are entangled, and the portion becomes a paper defect, and a uniform wet nonwoven fabric (paper) is formed. It tends to be difficult to obtain.
また、本発明の湿式不織布はバインダー繊維に加え、ポリエステル延伸繊維などの主体繊維を混抄して製造することも好ましい。 In addition, the wet nonwoven fabric of the present invention is preferably produced by blending main fibers such as stretched polyester fibers in addition to binder fibers.
湿式不織布を構成する繊維におけるバインダー繊維の混抄率（質量比率）としては５％以上、さらには３０〜５０質量％の範囲にあることが好ましい。バインダー繊維の含量が少なすぎると、湿式不織布の形態を構成する繊維本数が極端に少なくなり、均一な不織布を製造できなくなったり、強度不足となる傾向にある。 The mixing ratio (mass ratio) of the binder fibers in the fibers constituting the wet nonwoven fabric is preferably 5% or more, and more preferably in the range of 30 to 50% by mass. When the content of the binder fiber is too small, the number of fibers constituting the wet nonwoven fabric is extremely reduced, and a uniform nonwoven fabric cannot be produced or the strength tends to be insufficient.
一般に、主体繊維とバインダー繊維から成る湿式不織布は、バインダー繊維の混抄率が高いと、カレンダー加工の際にバインダー繊維がフィルム化し、不織布の特性である通気性を損なうおそれがあるが、本発明においてはより低い結晶化温度を持つ繊維をバインダー繊維として用いるために、それを防止することが可能となった。 In general, a wet nonwoven fabric composed of a main fiber and a binder fiber has a high blending ratio of the binder fiber, and the binder fiber becomes a film during calendering, which may impair the air permeability that is a characteristic of the nonwoven fabric. Made it possible to prevent the use of fibers having a lower crystallization temperature as binder fibers.
このような本発明の湿式不織布は、抄紙工程によって製造することができる。より具体的には、パルパー中に繊維を分散させ、その後、長網抄紙方式、円網抄紙方式、短網抄紙方式、あるいはこれらを複数台組み合わせて多層抄きにすることも好ましい。より均一な湿式不織布とするためには、パルパー中に分散剤や消泡剤を添加することも好ましい。このような分散剤としては例えばポリエステル系の水分散物（例えば高松油脂株式会社製の「ＤＴ―１００」）などが好ましく使用される。 Such a wet nonwoven fabric of the present invention can be produced by a papermaking process. More specifically, it is also preferable to disperse the fibers in the pulper, and then to make a multi-layered paper by using a long net paper making method, a circular net paper making method, a short net paper making method, or a combination of a plurality of these. In order to obtain a more uniform wet nonwoven fabric, it is also preferable to add a dispersant or an antifoaming agent to the pulper. As such a dispersant, for example, a polyester-based aqueous dispersion (for example, “DT-100” manufactured by Takamatsu Yushi Co., Ltd.) is preferably used.
抄紙後の乾燥工程は、常法にしたがい、ヤンキードライヤー、エアスルードライヤーなどを用いることができる。乾燥温度は、７０〜１５０℃の範囲であることが好ましい。さらに好ましくは８０〜１２０℃の範囲であることが好ましい。乾燥温度が低すぎる場合は、乾燥が不十分となり、最終的に湿式不織布の強度が不足する傾向にある。逆に、乾燥温度が高すぎる場合、バインダー繊維が結晶化し、最終的に湿式不織布の強度が低下する傾向にある。 The drying process after papermaking can use a Yankee dryer, an air through dryer, etc. according to a conventional method. The drying temperature is preferably in the range of 70 to 150 ° C. More preferably, it is in the range of 80 to 120 ° C. When the drying temperature is too low, the drying becomes insufficient, and the strength of the wet nonwoven fabric tends to be insufficient. On the other hand, when the drying temperature is too high, the binder fibers are crystallized, and the strength of the wet nonwoven fabric tends to decrease.
本発明の湿式不織布の製造方法としては、上記のように常法にて抄紙された後、紙強度を向上させるためにカレンダー加工により熱プレスすることが好ましい。この時用いるカレンダーロールとしては、金属／金属ロール、金属／ペーパーロール、金属／弾性ロールなどを用いることが好ましい。 As a method for producing the wet nonwoven fabric of the present invention, it is preferable to carry out hot pressing by calendering in order to improve paper strength after the paper is made by a conventional method as described above. As a calendar roll used at this time, it is preferable to use a metal / metal roll, a metal / paper roll, a metal / elastic roll, or the like.
このようなカレンダーによる熱処理において、そのカレンダープレスの温度としては１００〜２５０℃の範囲内であることが好ましい。より好ましくは１５０〜２５０℃、特に好ましくは１７０〜２３０℃の範囲内である。温度が低すぎる場合には、繊維が潰れにくくなり湿式不織布の強度が発現しにくい傾向にある。逆に温度が高すぎると、繊維が融解しやすくなり不均一な湿式不織布となる傾向にある。カレンダー熱処理時のプレス圧力としては１００〜２５００Ｎ／ｃｍ（１０〜２５５ｋｇｆ／ｃｍ）の範囲内であることが好ましく、さらに好ましくは３００〜２２００Ｎ／ｃｍ（３１〜２２４ｋｇｆ／ｃｍ）、特には４００〜２０００Ｎ／ｃｍ（４１〜２０４ｋｇｆ／ｃｍ）の範囲であることが好ましい。 In such a heat treatment using a calendar, the temperature of the calendar press is preferably in the range of 100 to 250 ° C. More preferably, it is 150-250 degreeC, Most preferably, it exists in the range of 170-230 degreeC. If the temperature is too low, the fibers are less likely to be crushed and the strength of the wet nonwoven fabric tends to be difficult to develop. On the other hand, if the temperature is too high, the fiber tends to melt and tends to be a non-uniform wet nonwoven fabric. The press pressure at the time of calender heat treatment is preferably within a range of 100 to 2500 N / cm (10 to 255 kgf / cm), more preferably 300 to 2200 N / cm (31 to 224 kgf / cm), particularly 400 to 2000 N. / Cm (41 to 204 kgf / cm) is preferable.
そして上述のような製造方法によって得られる本発明の湿式不織布としては、その目付が１〜３０ｇ／ｍ２の範囲であることが好ましい。さらに好ましくは２〜１５ｇ／ｍ２の範囲であることが、特には３〜１２ｇ／ｍ２の範囲であることが好ましい。目付が大きすぎると湿式不織布を構成する繊維の本数が多すぎて、通気度や孔径が極端に低下し、不織布の特性が低下する傾向にある。 And as a wet nonwoven fabric of this invention obtained by the above manufacturing methods, it is preferable that the fabric weight is the range of 1-30 g / m < 2 >. More preferably, it is in the range of 2 to 15 g / m 2 , and particularly preferably in the range of 3 to 12 g / m 2 . If the basis weight is too large, the number of fibers constituting the wet nonwoven fabric is too large, the air permeability and the pore diameter are extremely lowered, and the properties of the nonwoven fabric tend to be lowered.
また本発明の湿式不織布の厚さはとしては、２０μｍ以下であることが好ましい。さらには５〜１７μｍの範囲であることが、特には１２〜１７μｍの範囲であることが好ましい。厚すぎると、カレンダー加工時にバインダー繊維がフィルム化しやすく、通気度や孔径が低下し、性能が低下する傾向にある。 Moreover, as thickness of the wet nonwoven fabric of this invention, it is preferable that it is 20 micrometers or less. Furthermore, it is preferable that it is the range of 5-17 micrometers, and it is especially preferable that it is the range of 12-17 micrometers. If it is too thick, the binder fiber is likely to be formed into a film at the time of calendering, and the air permeability and pore diameter are lowered, and the performance tends to be lowered.
湿式不織布の密度としては１ｇ／ｃｍ３以下であることが好ましく、より好ましくは０．５〜０．９ｇ／ｃｍ３の範囲であることが好ましい。密度が高すぎても、不織布が樹脂化してフィルムライクとなりやすい傾向にあり、不織布の特性を損なわれる傾向にある。 Preferably the density of the wet nonwoven fabric is 1 g / cm 3 or less, and more preferably in the range of 0.5~0.9g / cm 3. Even if the density is too high, the nonwoven fabric tends to be resinized and easily film-like, and the properties of the nonwoven fabric tend to be impaired.
本発明の湿式不織布の通気度としては１．８〜３６ｃｍ３／（ｃｍ２・ｓｅｃ）の範囲であることが好ましい。さらに好ましくは２０ｃｍ３／（ｃｍ２・ｓｅｃ）以下、特に好ましくは１０ｃｍ３／（ｃｍ２・ｓｅｃ）以下、もっとも好ましくは１・８〜５ｃｍ３／（ｃｍ２・ｓｅｃ）の範囲にあることが好ましい。通気度は不織布の特性を確保するためにも必要であるが、逆に通気度が大きすぎる場合には、湿式不織布の強度が低下する傾向にある。 The air permeability of the wet nonwoven fabric of the present invention is preferably in the range of 1.8 to 36 cm 3 / (cm 2 · sec). More preferably, it is 20 cm 3 / (cm 2 · sec) or less, particularly preferably 10 cm 3 / (cm 2 · sec) or less, most preferably in the range of 1.8 to 5 cm 3 / (cm 2 · sec). preferable. The air permeability is necessary to ensure the properties of the nonwoven fabric. Conversely, when the air permeability is too high, the strength of the wet nonwoven fabric tends to decrease.
このような本発明の湿式不織布は貫通孔を有することが好ましく、貫通孔の平均孔径としては０．１〜５．０μｍの範囲内であることが好ましい。さらに好ましくは０．５〜３．０μｍ、より好ましくは０．８〜２．０μｍの範囲であることが好ましい。平均孔径が小さすぎるとフィルムライクとなり、不織布の特徴である多孔性を維持しにくい傾向にある。逆に、平均孔径が大きすぎると、不織布の地合いが悪くなり、均一性を損なう傾向にある。また、貫通孔の最小孔径としては０．０１〜１．５μｍの範囲であることが好ましい。より好ましくは０．０１〜１．２μｍ、特に好ましくは０．０５〜１．０μｍの範囲であることが好ましい。最小孔径が小さすぎると、フィルムライクとなり、不織布の特徴である多孔性を維持しにくい傾向にある。さらに、最大孔径／平均孔径の値が１０以下、特には１〜６の範囲であることが好ましい。最大孔径／平均孔径の値が小さいほど、不織布の地合い・均一性が向上する。 Such a wet nonwoven fabric of the present invention preferably has through holes, and the average hole diameter of the through holes is preferably in the range of 0.1 to 5.0 μm. More preferably, it is 0.5-3.0 micrometers, More preferably, it is preferable that it is the range of 0.8-2.0 micrometers. If the average pore diameter is too small, the film is like a film, and it tends to be difficult to maintain the porosity characteristic of the nonwoven fabric. Conversely, if the average pore diameter is too large, the texture of the nonwoven fabric tends to deteriorate and the uniformity tends to be impaired. Further, the minimum hole diameter of the through hole is preferably in the range of 0.01 to 1.5 μm. More preferably, it is 0.01 to 1.2 μm, and particularly preferably 0.05 to 1.0 μm. If the minimum pore size is too small, the film becomes like a film, and it tends to be difficult to maintain the porosity characteristic of the nonwoven fabric. Further, the value of the maximum pore diameter / average pore diameter is preferably 10 or less, particularly preferably in the range of 1 to 6. The smaller the value of the maximum pore diameter / average pore diameter, the better the texture and uniformity of the nonwoven fabric.
本発明の湿式不織布のたて方向の引張強さは１．０Ｎ／１５ｍｍ巾以上あることが好ましく、特には１．０〜７．５Ｎ／１５ｍｍ巾の範囲内であることが好ましい。 The tensile strength in the vertical direction of the wet nonwoven fabric of the present invention is preferably 1.0 N / 15 mm width or more, and particularly preferably in the range of 1.0 to 7.5 N / 15 mm width.
そしてこのような本発明の湿式不織布は、機械的特性、電気的特性、耐熱性、寸法安定性、疎水性等の優れた物性に優れたものであって、熱カレンダー処理によってもフィルム化しにくく、高い通気性を維持する湿式不織布である。特に本発明の湿式不織布は均一性や多孔性に優れ、特にフィルターやセパレータなどの低目付の用途において、特に有用である。 And such a wet nonwoven fabric of the present invention has excellent physical properties such as mechanical properties, electrical properties, heat resistance, dimensional stability, hydrophobicity, and is difficult to be formed into a film by thermal calendering, It is a wet nonwoven fabric that maintains high air permeability. In particular, the wet nonwoven fabric of the present invention is excellent in uniformity and porosity, and is particularly useful for low-weight applications such as filters and separators.
本発明の実施例及び比較例を詳述するが、本発明はこれらによって限定されるものではない。なお、実施例中の各測定項目は下記の方法で測定した。 Examples and Comparative Examples of the present invention will be described in detail, but the present invention is not limited thereto. In addition, each measurement item in an Example was measured with the following method.
（１）ポリエステル繊維の結晶化温度
ＴＡインスツルメント・ジャパン（株）社製のサーマル・アナリスト２２００を使用し、昇温速度２０℃／分で測定し、ＪＩＳ Ｋ７１２１−１９８７に記載の方法で測定を行った。
(1) Crystallization temperature of polyester fiber Using a thermal analyst 2200 manufactured by TA Instruments Japan Co., Ltd., the temperature is measured at a temperature rising rate of 20 ° C./min, and the method described in JIS K7121-1987. Measurements were made.
（２）ポリエステル繊維の繊度
ＪＩＳ Ｌ１０１５：２０１０ ８．５．１ Ｂ法に記載の方法により測定した。
(2) Fineness of polyester fiber It measured by the method as described in JIS L1015: 2010 8.5.1 B method.
（３）湿式不織布の目付
ＪＩＳ Ｐ８１２４（紙及び板紙 坪量の測定方法）に基づいて実施し、小数点以下第二位を四捨五入して求めた。
(3) Weight per unit area of wet nonwoven fabric It was determined based on JIS P8124 (paper and paperboard basis weight measurement method), and rounded off to the second decimal place.
（４）湿式不織布の厚さおよび密度
ＪＩＳ Ｐ８１１８（紙及び板紙 厚さ、密度の試験方法）に基づいて実施した。
(4) Thickness and density of wet nonwoven fabric The test was carried out based on JIS P8118 (paper and paperboard thickness and density test method).
（５）湿式不織布の通気度
ＪＩＳ Ｌ１９１３（一般不織布試験方法 通気性 フラジール形法）に基づいて測定した。
(5) Air permeability of wet nonwoven fabric It measured based on JIS L1913 (General nonwoven fabric test method Breathability fragile type method).
（６）湿式不織布の引張強さ
ＪＩＳ Ｐ８１１３（紙及び板紙 引張特性の試験方法）に基づいてＭＤ方向（縦方向）の引張強さを測定し、最大点荷重（Ｎ／１５ｍｍ巾）を示した。
(6) Tensile strength of wet nonwoven fabric The tensile strength in the MD direction (longitudinal direction) was measured based on JIS P8113 (paper and paperboard tensile property test method), and the maximum point load (N / 15 mm width) was shown. .
（７）湿式不織布の貫通孔の孔径
直径２．５ｃｍの円形サンプルを不織布からランダムに２点採取し、パーム・ポロメーター（ＰＭＩ社製、細孔径分布測定器）を用いて平均孔径、最大孔径、最小孔径を測定し、小数点以下第二位を四捨五入して求めた。最大孔径／平均孔径の値を計算し、孔径ばらつきとした。
(7) Pore diameter of through-holes of wet nonwoven fabric Two circular samples with a diameter of 2.5 cm were randomly collected from the nonwoven fabric, and average pore diameter and maximum pore diameter were measured using a palm porometer (manufactured by PMI, pore diameter distribution measuring instrument). The minimum pore diameter was measured and calculated by rounding off the second decimal place. The value of the maximum pore diameter / average pore diameter was calculated and defined as the pore diameter variation.
［実施例１〜３］
固有粘度０．４７ｄＬ／ｇのポリエチレンテレフタレート（Ｔｇ７０℃）を１７０℃で乾燥後、スクリュー式押出機を装備した溶融紡糸装置にて２９０℃で溶融し、２５０４個の吐出孔を穿設した紡糸口金を通して、３４０ｇ／分で吐出し、５００ｍ／分の速度で引取り、未延伸ポリエステル繊維束を得た。該未延伸ポリエステル繊維束を、８５℃温水中で、３４倍の条件下でフロー延伸を行い、フロー延伸された繊度０．０８ｄｔｅｘのポリエステル系のバインダー繊維を得た。さらに３ｍｍの繊維長にカットして、抄紙用のバインダー繊維とした。このバインダー繊維の結晶化温度は１０９℃、融点は２５７℃であった。
[Examples 1 to 3]
A spinneret having an intrinsic viscosity of 0.47 dL / g polyethylene terephthalate (Tg 70 ° C.) dried at 170 ° C., melted at 290 ° C. in a melt spinning apparatus equipped with a screw extruder, and provided with 2504 discharge holes. Through, it discharged at 340 g / min and picked up at a speed | rate of 500 m / min, and obtained the unstretched polyester fiber bundle. The unstretched polyester fiber bundle was flow-stretched in 85 ° C. warm water under conditions of 34 times to obtain a flow-stretched polyester binder fiber having a fineness of 0.08 dtex. Further, it was cut into a fiber length of 3 mm to obtain a binder fiber for papermaking. The binder fiber had a crystallization temperature of 109 ° C. and a melting point of 257 ° C.
一方、上記の過程で得られた３４倍のフロー延伸後の部分延伸ポリエステル繊維束を、７０℃の温水中で、さらに２．５倍の条件のネック延伸を行い、さらに９５℃の温水中で５％の制限収縮処理を行って、繊度０．０４ｄｔｅｘのポリエステル延伸繊維を得た。さらに３ｍｍの繊維長にカットして、抄紙用の延伸繊維とした。この延伸繊維の結晶化温度は観察されず、融点は２５５℃であった。 On the other hand, the partially stretched polyester fiber bundle after the 34-fold flow stretching obtained in the above process is subjected to neck stretching under conditions of 2.5 times in warm water at 70 ° C, and further in warm water at 95 ° C. 5% limited shrinkage treatment was performed to obtain a stretched polyester fiber having a fineness of 0.04 dtex. Further, it was cut into a fiber length of 3 mm to obtain a drawn fiber for papermaking. The crystallization temperature of this drawn fiber was not observed, and the melting point was 255 ° C.
得られたポリエステル系のバインダー繊維およびポリエステル系の延伸繊維を、表１に示す目付・混抄率となるように量りとり、水中に分散させミキサーで強撹拌してスラリーとした。その後、スラリーをタッピ抄紙機に移し、スラリーにポリエステル樹脂を主成分とする分散剤（高松油脂株式会社製、「ＤＴ−１００」）を０．１％となるよう添加し、充分撹拌した。水を除去してメッシュ上にてシート化させ、ロータリードライヤーを用いて表１に示す温度で乾燥し、原紙を抄造した。得られた原紙を、加熱金属ロールと弾性ロールの組み合わせのカレンダー装置を用いて、表１に示す条件で熱カレンダー加工を施し、湿式不織布を得て、そのものの物性評価をした。評価結果を併せて、表１に示す。 The obtained polyester-based binder fibers and polyester-based drawn fibers were weighed so as to have the basis weight / mixing ratio shown in Table 1, dispersed in water, and vigorously stirred with a mixer to obtain a slurry. Thereafter, the slurry was transferred to a tappi paper machine, and a dispersant mainly composed of a polyester resin (manufactured by Takamatsu Yushi Co., Ltd., “DT-100”) was added to the slurry so as to be 0.1%, and sufficiently stirred. Water was removed to form a sheet on the mesh, and dried at a temperature shown in Table 1 using a rotary dryer to produce a base paper. The obtained base paper was subjected to thermal calendering under the conditions shown in Table 1 using a calender device in which a heated metal roll and an elastic roll were combined to obtain a wet nonwoven fabric, and its physical properties were evaluated. The evaluation results are also shown in Table 1.
［比較例１］
固有粘度間０．４７ｄＬ／ｇのポリエチレンテレフタレート（Ｔｇ７０℃）を１７０℃で乾燥後、スクリュー式押出機を装備した溶融紡糸装置にて２９０℃で溶融し、２５０４個の吐出孔を穿設した紡糸口金を通して、３４０ｇ／分で吐出し、５００ｍ／分の速度で引取り、未延伸ポリエステル繊維束を得た。該未延伸ポリエステル繊維束を、８５℃温水中で１３倍の条件下でフロー延伸を行い、フロー延伸された繊度０．２ｄｔｅｘのポリエステル系のバインダー繊維を得た。さらに３ｍｍの繊維長にカットして、抄紙用のバインダー繊維とした。このバインダー繊維の結晶化温度は１３２℃、融点は２５７℃であった。
[Comparative Example 1]
Polyethylene terephthalate (Tg 70 ° C.) having an intrinsic viscosity of 0.47 dL / g was dried at 170 ° C. and then melted at 290 ° C. in a melt spinning apparatus equipped with a screw type extruder, and spinning with 2504 discharge holes formed therein. It was discharged at 340 g / min through the die, and taken up at a speed of 500 m / min to obtain an unstretched polyester fiber bundle. The unstretched polyester fiber bundle was subjected to flow stretching in 85 ° C. warm water under a condition of 13 times to obtain a flow-stretched polyester binder fiber having a fineness of 0.2 dtex. Further, it was cut into a fiber length of 3 mm to obtain a binder fiber for papermaking. The binder fiber had a crystallization temperature of 132 ° C. and a melting point of 257 ° C.
一方、抄紙用のポリエステル系の延伸繊維としては、実施例１等と同じものを用いた。
その後、実施例１等と同様の方法にて、ただし表１記載の条件にて湿式不織布を得た後、物性評価をした。評価結果を表１に示す。
On the other hand, as the polyester-based drawn fibers for papermaking, the same ones as in Example 1 were used.
Thereafter, in the same manner as in Example 1 etc., but after obtaining a wet nonwoven fabric under the conditions described in Table 1, physical properties were evaluated. The evaluation results are shown in Table 1.
表１から明らかな通り、０．２ｄｔｅｘ未満の繊度のバインダー繊維を用いた本発明の湿式不織布は、貫通孔の孔径が小さく、かつ緻密であるにもかかわらず、通気度の高い不織布が得られている。これは、細繊度のバインダー繊維、さらには繊維長の短いバインダー繊維が、不織布製造工程中のカレンダー熱処理工程で結晶化し、そのカレンダー加工の際に繊維形状を維持したためであると考えられる。他方、比較例で用いている太繊度のバインダー繊維は、得られた湿式不織布の平均孔径が高いにもかかわらず通気度が低いことから、実施例に比べて均一性が劣り、部分的にフィルムライクとなっている、あるいは、湿式不織布の特性である多孔性が損なわれているもの、と考えられる。 As is apparent from Table 1, the wet nonwoven fabric of the present invention using binder fibers having a fineness of less than 0.2 dtex provides a nonwoven fabric with high air permeability despite the small diameter of the through-holes and the denseness. ing. This is presumably because the binder fiber having a fineness and further the binder fiber having a short fiber length were crystallized in the calender heat treatment process in the nonwoven fabric manufacturing process, and the fiber shape was maintained during the calendering process. On the other hand, the binder fiber having a large fineness used in the comparative example has low air permeability despite the high average pore diameter of the obtained wet nonwoven fabric. It is thought that the porosity which is like or the characteristic of the wet nonwoven fabric is impaired.
以上に説明した本発明の湿式不織布は、種々の加工方法を適用することができ、幅広い生活資材、及び、産業資材用途に使用することできる。ろ過膜や、セパレータの基材、高性能フィルターに供することができる。
Various processing methods can be applied to the wet nonwoven fabric of the present invention described above, and it can be used for a wide range of life materials and industrial materials. It can be used for filtration membranes, separator substrates, and high performance filters.
Claims (8)
The wet weight according to any one of claims 1 to 7, wherein the basis weight of the wet nonwoven fabric is in the range of 1 to 30 g / m 2 , and the air permeability is in the range of 1.8 to 36 cm 3 / (cm 2 · sec). Non-woven fabric.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018106853A JP7148280B2 (en) | 2018-06-04 | 2018-06-04 | wet nonwoven fabric |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2018106853A JP7148280B2 (en) | 2018-06-04 | 2018-06-04 | wet nonwoven fabric |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2019210567A true JP2019210567A (en) | 2019-12-12 |
| JP7148280B2 JP7148280B2 (en) | 2022-10-05 |
Family
ID=68846433
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2018106853A Active JP7148280B2 (en) | 2018-06-04 | 2018-06-04 | wet nonwoven fabric |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP7148280B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113699797A (en) * | 2021-09-02 | 2021-11-26 | 前沿新材料研究院（深圳）有限公司 | Composite non-woven fabric and preparation method thereof, electromagnetic shielding film and integrated circuit board |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1990004666A1 (en) * | 1988-10-28 | 1990-05-03 | Teijin Limited | Wet-process nonwoven fabric and ultrafine polyester fibers therefor |
| JPH05163650A (en) * | 1991-12-13 | 1993-06-29 | Teijin Ltd | Production of nonwoven fabric |
| JP2002095937A (en) * | 2000-09-22 | 2002-04-02 | Hour Seishi Kk | Semipermeable membrane support and its manufacturing method |
| JP2003313726A (en) * | 2002-04-25 | 2003-11-06 | Teijin Ltd | Polyester fiber for papermaking and method for producing the same |
| WO2008130020A1 (en) * | 2007-04-18 | 2008-10-30 | Teijin Fibers Limited | Thin paper |
| JP2010180513A (en) * | 2009-02-09 | 2010-08-19 | Daio Paper Corp | Substrate for adhesive tape |
| JP2012092461A (en) * | 2010-10-27 | 2012-05-17 | Teijin Fibers Ltd | Thin paper |
| JP2012161725A (en) * | 2011-02-04 | 2012-08-30 | Daio Paper Corp | Semipermeable membrane support, semipermeable membrane for water treatment, and method for manufacturing semipermeable membrane support |
| JP2013136851A (en) * | 2011-12-28 | 2013-07-11 | Kuraray Co Ltd | Polyester-based conjugate binder fiber |
| WO2014123033A1 (en) * | 2013-02-05 | 2014-08-14 | 三菱製紙株式会社 | Nonwoven substrate for lithium-ion secondary cell separator, and lithium-ion secondary cell separator |
| JP2014197995A (en) * | 2013-03-29 | 2014-10-23 | 大王製紙株式会社 | Mulching sheet |
| WO2015152082A1 (en) * | 2014-03-31 | 2015-10-08 | 株式会社クラレ | Polyester binder fibers |
| WO2017159216A1 (en) * | 2016-03-15 | 2017-09-21 | 帝人株式会社 | Filter medium for liquid filter and liquid filter |
-
2018
- 2018-06-04 JP JP2018106853A patent/JP7148280B2/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1990004666A1 (en) * | 1988-10-28 | 1990-05-03 | Teijin Limited | Wet-process nonwoven fabric and ultrafine polyester fibers therefor |
| JPH05163650A (en) * | 1991-12-13 | 1993-06-29 | Teijin Ltd | Production of nonwoven fabric |
| JP2002095937A (en) * | 2000-09-22 | 2002-04-02 | Hour Seishi Kk | Semipermeable membrane support and its manufacturing method |
| JP2003313726A (en) * | 2002-04-25 | 2003-11-06 | Teijin Ltd | Polyester fiber for papermaking and method for producing the same |
| WO2008130020A1 (en) * | 2007-04-18 | 2008-10-30 | Teijin Fibers Limited | Thin paper |
| JP2010180513A (en) * | 2009-02-09 | 2010-08-19 | Daio Paper Corp | Substrate for adhesive tape |
| JP2012092461A (en) * | 2010-10-27 | 2012-05-17 | Teijin Fibers Ltd | Thin paper |
| JP2012161725A (en) * | 2011-02-04 | 2012-08-30 | Daio Paper Corp | Semipermeable membrane support, semipermeable membrane for water treatment, and method for manufacturing semipermeable membrane support |
| JP2013136851A (en) * | 2011-12-28 | 2013-07-11 | Kuraray Co Ltd | Polyester-based conjugate binder fiber |
| WO2014123033A1 (en) * | 2013-02-05 | 2014-08-14 | 三菱製紙株式会社 | Nonwoven substrate for lithium-ion secondary cell separator, and lithium-ion secondary cell separator |
| JP2014197995A (en) * | 2013-03-29 | 2014-10-23 | 大王製紙株式会社 | Mulching sheet |
| WO2015152082A1 (en) * | 2014-03-31 | 2015-10-08 | 株式会社クラレ | Polyester binder fibers |
| WO2017159216A1 (en) * | 2016-03-15 | 2017-09-21 | 帝人株式会社 | Filter medium for liquid filter and liquid filter |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113699797A (en) * | 2021-09-02 | 2021-11-26 | 前沿新材料研究院（深圳）有限公司 | Composite non-woven fabric and preparation method thereof, electromagnetic shielding film and integrated circuit board |
Also Published As
| Publication number | Publication date |
|---|---|
| JP7148280B2 (en) | 2022-10-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101421317B1 (en) | Wet-laid non-woven fabric and filter | |
| KR101441723B1 (en) | Thin paper | |
| KR20180121613A (en) | Filter for liquid filter and liquid filter | |
| TWI686520B (en) | Polyester binder fiber | |
| WO2013094268A1 (en) | Filtration material for filter, method for manufacturing same, and filter | |
| JP4616658B2 (en) | Non-woven | |
| JP2014074246A (en) | Wet nonwoven fabric for liquid filtration filter and liquid filtration filter | |
| JP4960908B2 (en) | Polyethylene naphthalate fiber and short fiber nonwoven fabric comprising the same | |
| JP7148280B2 (en) | wet nonwoven fabric | |
| JP2012237084A (en) | Nonwoven fabric for filter and air filter | |
| JP4647341B2 (en) | Polyester fiber paper for heat sensitive stencil paper | |
| JP2004181341A (en) | Wet nonwoven fabric for filter and polyester binder fiber for use therein | |
| JP2020172034A (en) | Water-absorbing vaporized material | |
| JP2009185417A (en) | Cellulose nano-fiber nonwoven sheet | |
| KR101242687B1 (en) | Polyester nonwoven fabrics and preparation method thereof | |
| JP6462368B2 (en) | Wet nonwovens and shoji paper and products | |
| JP6715352B2 (en) | Polyester binder fiber | |
| JP2012067408A (en) | Wet type polyester nonwoven fabric | |
| JP2019210566A (en) | Polyester-based binder fiber | |
| JP6534885B2 (en) | Stretched polyester-based fiber and fiber structure containing the fiber | |
| JP7264618B2 (en) | Polyester heat-fusible fiber, method for producing the same, and wet-laid nonwoven fabric using the same | |
| JP2013122101A (en) | Wet nonwoven fabric | |
| JP5689626B2 (en) | Wet short fiber nonwoven fabric | |
| WO2021132411A1 (en) | Spun-bonded nonwoven fabric, multilayer filter medium, filter medium for pleated filters, and pleated filter | |
| JP2012112079A (en) | Polyethylene naphthalate fiber and staple fiber nonwoven fabric therefrom |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20210323 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20211116 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20211124 |
|
| A601 | Written request for extension of time |
Free format text: JAPANESE INTERMEDIATE CODE: A601 Effective date: 20220118 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20220311 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20220531 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20220610 |
|
| 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: 20220906 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20220922 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 7148280 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |