JP3553722B2 - Biodegradable nonwoven fabric and method for producing the same - Google Patents
Biodegradable nonwoven fabric and method for producing the same Download PDFInfo
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- JP3553722B2 JP3553722B2 JP05111596A JP5111596A JP3553722B2 JP 3553722 B2 JP3553722 B2 JP 3553722B2 JP 05111596 A JP05111596 A JP 05111596A JP 5111596 A JP5111596 A JP 5111596A JP 3553722 B2 JP3553722 B2 JP 3553722B2
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Images
Landscapes
- Spinning Methods And Devices For Manufacturing Artificial Fibers (AREA)
- Polyesters Or Polycarbonates (AREA)
- Nonwoven Fabrics (AREA)
- Cleaning Implements For Floors, Carpets, Furniture, Walls, And The Like (AREA)
- Absorbent Articles And Supports Therefor (AREA)
- Laminated Bodies (AREA)
- Biological Depolymerization Polymers (AREA)
- Artificial Filaments (AREA)
- Multicomponent Fibers (AREA)
Description
【０００１】
【発明の属する技術分野】
本発明は、医療・衛生材料、生活資材あるいは一般産業資材など、幅広い用途に用いられる生分解性不織布およびその製造方法に関するものである。
【０００２】
【従来の技術】
生分解性不織布としては、例えば、コットン、麻、羊毛、レーヨン、キチン、アルギン酸等のような天然繊維由来の生分解性不織布が知られている。しかし、これらの生分解性不織布は一般的に親水性であり、優れた吸水性を有するものであるが、反面、これらの不織布は湿潤環境下での強力や寸法安定性の低下が著しく、一部の用途への展開には限界があった。さらに、これらの不織布は非熱可塑性であることから、熱成形性を有さず加工性に劣るものであった。
【０００３】
これらの問題を解決する生分解性不織布としては、特開平５−９３３１８号公報または特開平５−１９５４０７号公報に生分解性を有する熱可塑性重合体を用いた不織布が開示されている。しかし、これらにおいては、紡出糸条の冷却性および可紡性に劣るためスパンボンド法による製造は困難であり、しかも全融タイプとなるので得られた不織布の機械的特性および柔軟性に劣るものであった。これは、一般的に生分解性を有する重合体の融点および結晶化温度が低く、しかも結晶化速度が遅いことに起因する。すなわち、溶融紡出後の冷却、牽引細化、捕集、堆積工程において、糸条間で密着が発生するために充分な開繊を行なうことができないため、得られる不織布の地合いを損なうこととなり、また生分解速度の制御も困難である等の問題を生じることとなる。
【０００４】
また、従来の、一成分のみから構成される単一型、単一中空型等の繊維横断面をもつ長繊維は、スパンボンド法による不織布の製造に際し、融点および結晶化温度の比較的高い生分解性を有する重合体を用いて紡出糸条の冷却性および開繊性を重視すると、得られる不織布の生分解性能に劣ることとなる。逆に、生分解性能を重視し融点および結晶化温度の比較的低い生分解性を有する重合体を用いると、紡出糸条の冷却性および開繊性が劣ることとなる。しかも、従来の方法では、生分解性能の制御は、適用する重合体の種類および繊度、複合比および繊維の配向度などを変更することにより幾分かは可能ではあるが、微妙な制御は不可能であった。
【０００５】
さらに、前述のような生分解性熱可塑性重合体を用いた長繊維単独で形成された不織布は、機械的特性には優れるものの、吸湿性、吸水性に劣り、用途が限定されるものであった。これを改善する方法としては、吸水性に優れる天然繊維等を積層することが考えられるが、生分解性熱可塑性重合体からなる長繊維不織ウエブと天然繊維からなる不織ウエブとを積層して部分熱融着を施す場合に、従来適用されているエンボスロールを用いた熱圧接装置によると、両ウエブ間の接着力が弱く、得られる積層不織布は到底使用に耐えるものではなかった。
【０００６】
【発明が解決しようとする課題】
本発明は、このような問題を解決するもので、生分解性能が制御可能であるとともに不織布の地合いおよび機械的特性、紡出糸条の冷却性および可紡性に優れ、かつ熱接着機能を有し、さらに必要に応じて吸水性をも発揮しうる生分解性不織布およびこれらの製造方法を提供しようとするものである。
【０００７】
【課題を解決するための手段】
この課題を解決するため本発明は、以下の構成を要旨とするものである。
（１）複合長繊維からなる長繊維不織ウエブが部分的に熱圧接されて所定の形態が保持されてなる不織布であって、前記複合長繊維が生分解性を有する第１の脂肪族ポリエステルからなる高融点成分とこの高融点成分よりも融点の低い生分解性を有する第２の脂肪族ポリエステルからなる低融点成分とから形成されるとともに牽引速度２０００ｍ／分以上で牽引細化された多葉型複合長繊維であり、この多葉型複合長繊維の繊維横断面において、低融点成分が芯部を形成し、高融点成分が前記低融点成分の円周方向に独立した突起部を複数形成し、しかも低融点成分は高融点成分によって分断されることなく連続しており、かつ、多葉型複合長繊維を形成する高融点成分および低融点成分はともに繊維軸方向に連続するとともに繊維表面において交互に露出してなることを特徴とする生分解性不織布。
【０００８】
（２）複合長繊維からなる長繊維不織ウエブと天然繊維からなる天然繊維不織ウエブとが積層され部分的な圧接により一体化され、前記複合長繊維が生分解性を有する第１の脂肪族ポリエステルからなる高融点成分とこの高融点成分よりも融点の低い生分解性を有する第２の脂肪族ポリエステルからなる低融点成分とから形成されるとともに牽引速度２０００ｍ／分以上で牽引細化された多葉型複合長繊維であり、この多葉型複合長繊維の繊維横断面において、低融点成分が芯部を形成し、高融点成分が前記低融点成分の円周方向に独立した突起部を複数形成し、しかも低融点成分は高融点成分によって分断されることなく連続しており、かつ、多葉型複合長繊維を形成する高融点成分および低融点成分はともに繊維軸方向に連続するとともに繊維表面において交互に露出してなることを特徴とする生分解性不織布。
【０００９】
（３）複合長繊維からなる長繊維不織ウエブが部分的に熱圧接されて所定の形態が保持されてなる不織布の製造方法であって、前記複合長繊維を生分解性を有する第１の脂肪族ポリエステルからなる高融点成分とこの高融点成分よりも融点の低い生分解性を有する第２の脂肪族ポリエステルからなる低融点成分とを用いて形成し、繊維横断面において低融点成分が芯部を形成し、繊維横断面において高融点成分が前記低融点成分の円周方向に独立した突起部を複数形成し、しかも繊維横断面において前記低融点成分は高融点成分によって分断されることなく連続しており、高融点成分および低融点成分がともに繊維軸方向に連続するとともに繊維表面において交互に露出するような多葉型複合長繊維を溶融紡糸し、この多葉型複合長繊維を牽引速度２０００ｍ／分以上で牽引細化した後、長繊維不織ウエブとなし、この長繊維不織ウエブを熱圧接装置により部分的に熱圧接させることを特徴とする生分解性不織布の製造方法。
【００１０】
（４）複合長繊維からなる長繊維不織ウエブと天然繊維からなる天然繊維不織ウエブとを積層して部分的に圧接することにより一体化し、前記複合長繊維を生分解性を有する第１の脂肪族ポリエステルからなる高融点成分とこの高融点成分よりも融点の低い生分解性を有する第２の脂肪族ポリエステルからなる低融点成分とを用いて形成し、繊維横断面において低融点成分が芯部を形成し、繊維横断面において高融点成分が前記低融点成分の円周方向に独立した突起部を複数形成し、しかも繊維横断面において前記低融点成分は高融点成分によって分断されることなく連続しており、高融点成分および低融点成分がともに繊維軸方向に連続するとともに繊維表面において交互に露出するような多葉型複合長繊維を溶融紡糸し、この多葉型複合長繊維を牽引速度２０００ｍ／分以上で牽引細化した後、長繊維不織ウエブとなし、この長繊維不織ウエブに常法にて別途作成した天然繊維の不織ウエブを積層した後に、超音波融着処理を施して両不織ウエブを部分的に融着させ一体化することを特徴とする生分解性不織布の製造方法。
【００１１】
本発明は以上の構成により、長繊維の繊維横断面において、生分解性能には劣るが冷却性および開繊性に優れる高融点成分を細分化し繊維外周部に位置させ、冷却性および開繊性には劣るが生分解性能に優れる低融点成分を中央部に位置させることにより、冷却性、開繊性および生分解性能のいずれにも優れる不織布を得るものである。
【００１２】
また、本発明の生分解性不織布のうち、長繊維不織ウエブと天然繊維不織ウエブとを積層した積層不織布は、天然繊維によって吸水性を発揮させるとともに、湿潤時の機械的強力に劣るという天然繊維の特性を長繊維不織ウエブによって補強するものである。しかも、長繊維不織ウエブは脂肪族ポリエステル系重合体から構成され、天然繊維不織ウエブはコットン等の分解性素材から構成されるため、本発明の積層不織布の構成素材は全て自然環境下で分解し得るものである。
【００１３】
【発明の実施の形態】
まず、本発明の生分解性不織布のうち、長繊維不織ウエブが部分的に熱圧接されて所定の形態を保持してなる長繊維不織布について説明する。
【００１４】
本発明に適用される長繊維は、生分解性を有する脂肪族ポリエステル２成分により形成される。すなわち、本発明に適用される長繊維は、高融点成分の脂肪族ポリエステルと低融点成分の脂肪族ポリエステルとで構成された複合長繊維である。一般に、高融点成分は、紡出糸条の冷却性および開繊性には優れるものの、結晶化度が高いため生分解性能には劣り、逆に、低融点成分は、紡出糸条の冷却性および開繊性には劣るものの、結晶化度が低いため生分解性能には優れる。例えば、繊維横断面が高融点成分単相の場合には、製糸性および不織布化には優れるものの、目標とする生分解性能を得ることができない。一方、繊維横断面が低融点成分単相の場合には、紡出糸条の冷却性に劣り不織布すら得ることができない。本発明によれば、長繊維の繊維横断面において、生分解性能には劣るが冷却性および開繊性に優れる高融点成分を細分化し繊維外周部に位置させ、冷却性および開繊性には劣るが生分解性能に優れる低融点成分を中央部に位置させることにより、冷却性、開繊性および生分解性能のいずれにも優れる不織布を得ることができるのである。
【００１５】
従って、本発明における長繊維では、高融点成分と低融点成分との融点差を５℃以上とすることが好ましく、さらに好ましくは１０℃以上とするのが良い。高融点成分と低融点成分との融点差が５℃未満であると、繊維横断面が単相の場合のような全融タイプに近づくため、次工程における不織布の部分熱圧接において低融点成分のみならず高融点成分であっても熱的なダメージを生じることとなり、得られる不織布は機械的特性と柔軟性とを伴せ持つことができないものとなる。
【００１６】
本発明における多葉型複合長繊維を形成する脂肪族ポリエステルとしては、例えば、ポリグリコール酸やポリ乳酸のようなポリ（α−ヒドロキシ酸）、または、ポリ（ε−カプロラクトン）、ポリ（β−プロピオラクトン）のようなポリ（ω−ヒドロキシアルカノエート）またはこれらを構成する繰り返し単位要素による共重合体が、さらに、ポリ−３−ヒドロキシプロピオネート、ポリ−３−ヒドロキシブチレート、ポリ−３−ヒドロキシカプロエート、ポリ−３−ヒドロキシヘプタノエート、ポリ−３−ヒドロキシオクタノエートのようなポリ（β−ヒドロキシアルカノエート）およびこれらを構成する繰り返し単位要素とポリ−３−ヒドロキシバリレートやポリ−４−ヒドロキシブチレートを構成する繰り返し単位要素との共重合体が挙げられる。また、ジオールとジカルボン酸の縮重合体からなるものとして、例えば、ポリエチレンオキサレート、ポリエチレンサクシネート、ポリエチレンアジペート、ポリエチレンアゼテート、ポリブチレンオキサレート、ポリブチレンサクシネート、ポリブチレンアジペート、ポリブチレンセバケート、ポリヘキサメチレンセバケート、ポリネオペンチルオキサレートまたはこれらを構成する繰り返し単位要素による共重合体が挙げられる。以上の脂肪族ポリエステルのなかでは、ポリ乳酸またはポリエチレンサクシネートまたはポリブチレンサクシネートまたはポリブチレンアジペートまたはポリブチレンセバケートまたはこれらを構成する繰り返し単位要素による共重合体が、製糸性および生分解性能に優れるなどの理由により、好適に用いられる。
【００１７】
さらに、前記脂肪族ポリエステルのなかでは、ブチレンサクシネートを主繰り返し単位とする共重合ポリエステルが特に好適であるが、このとき、ブチレンサクシネートの共重合量比は、高融点成分としては８０モル％以上、低融点成分としては７０〜９０モル％であることが好ましい。ブチレンサクシネートの共重合量比が低すぎると、生分解性能には優れるものの、紡出糸条の冷却性および開繊性に劣り、目的とする長繊維ひいては不織布が得られないこととなる。逆に、ブチレンサクシネートの共重合量比が高すぎると、冷却性および開繊性には優れるものの、生分解性能に劣り本発明の目的とするものではない。
【００１８】
本発明で適用する重合体のメルトフロレート値（以降、ＭＦＲ値と記す）は、高融点成分および低融点成分のＭＦＲ値が１〜１００ｇ／１０分であることが好まく、さらには、高融点成分が１５〜５０ｇ／１０分であり、低融点成分が２０〜７０ｇ／１０分であることが好ましい。但し、本発明におけるＭＦＲ値は、ＡＳＴＭ−Ｄ−１２３８（Ｅ）記載の方法に準じて測定したものである。高融点成分のＭＦＲ値が１５ｇ／１０分未満および／または低融点成分のＭＦＲ値が２０ｇ／１０分未満であると、あまりにも高粘度であるため、紡出糸条の細化がスムーズでなく操業性を損なう結果となり、しかも得られる繊維は太繊度で均斉度に劣るものとなる。逆に、高融点成分のＭＦＲ値が５０ｇ／１０分および／または低融点成分のＭＦＲ値が７０ｇ／１０分を超えると、あまりにも低粘度であるため、複合断面が不安定となるばかりか、紡糸工程において糸切れが発生し操業性を損なうとともに、得られる不織布の機械的特性が劣る結果となる。これらの理由により、高融点成分のＭＦＲ値は１２〜４５ｇ／１０分、低融点成分のＭＦＲ値は１８〜６５ｇ／１０分であることがさらに好適である。
【００１９】
また、高融点成分の粘度は低融点成分の粘度より高い方が好ましい。一般に、熱可塑性重合体の複合紡糸において得られる繊維横断面は、低粘度成分が高粘度成分を被覆しようとする力が働く。つまり、本発明においては、高融点成分を高粘度にすることにより、円周方向における高融点成分は独立させやすく、さらには異形度を上げるのにも好適となる。
【００２０】
本発明において、高融点成分および低融点成分に適用される脂肪族ポリエステルは、数平均分子量が約２０，０００以上、好ましくは４０，０００以上、さらに好ましくは６０，０００以上のものが、製糸性および得られる糸条の特性の点で良い。また、重合度を高めるために少量のジイソシアネートやテトラカルボン酸二無水物などで鎖延長したものでも良い。
【００２１】
本発明において適用される長繊維においては、その構成成分のうちの少なくとも低融点成分中に結晶核剤が添加されていることが好ましい。結晶核剤を添加することにより、溶融紡出後に固化しにくい結晶性の低い重合体であっても、紡出糸条間に密着が発生するのを防止することができる。また、結晶核剤は、重合工程あるいは溶融工程で添加するが、その際、得られる糸の機械的性能および均斉度を向上させるため、できる限り均一分散させておくことが好ましい。
【００２２】
結晶核剤としては、粉末状の無機物で、かつ溶融液に溶解したりするものでなければ特に制限をうけないが、タルク、炭酸カルシウム、酸化チタン、窒化ホウ素、シリカゲル、酸化マグネシウムなどが通常用いられ、これらの中でも特に、タルクまたは酸化チタンまたはこれらの混合物が好適に用いられる。
【００２３】
結晶核剤としての無機粉末の平均粒径は５μｍ以下であるのが好ましい。平均粒径が５μｍを超えると、繊度のより細かな繊維が得られにくくなる傾向が生じたり、あるいは吐出孔を複数備えている紡糸口金内の濾過フィルターに目詰まりが発生しやすくなり、紡糸操業性が低下する傾向が生じる。これら理由により、結晶核剤としての無機粉末の平均粒径は５μｍ以下、好ましくは４μｍ以下、さらに好ましくは３μｍ以下が良い。
【００２４】
結晶核剤としての無機粉末の嵩比容は、２〜１０ｃｃ／ｇであるのが好ましく、３〜８ｃｃ／ｇであるのがより好ましい。なお、嵩比容は、単位重量当りの無機粉末の体積のことである。嵩比容が大きくなればなるほど、無機粉末の表面積が大きくなり、結晶核剤としての効果を増大させることになる。無機粉末の嵩比容が２ｃｃ／ｇ未満であると、結晶核剤としての効果が低減し、そのために結晶核剤の添加量（重合体中への含有量）を多くしなければならず、得られる長繊維ひいては不織布の機械的強度は低下する。また、嵩比容が１０ｃｃ／ｇを超える無機粉末の製造は困難であり、このような無機粉末を得ようとすると、無機粉末のコストが高騰し、ひいては得られる長繊維のコストも高騰する結果となる。
【００２５】
また、結晶核剤は、高融点成分中への結晶核剤の添加量をＱＡ （重量％）とし、低融点成分中への結晶核剤の添加量をＱＢ （重量％）としたときに、（１）式および（２）式を満足するように添加されていることが好ましい。
［（ΔＴＡ ＋ΔＴＢ）／１００］−２ ／３ ≦ＱＡ ＋ＱＢ ≦［（ΔＴＡ ＋ΔＴＢ）／１００］＋４…（１）
ＱＡ ≦ＱＢ …（２）
但し、ΔＴＡ ＝高融点成分の融点−高融点成分の結晶化温度≧３５
ΔＴＢ ＝低融点成分の融点−低融点成分の結晶化温度≧３５
結晶核剤の全添加量ＱＡ ＋ＱＢ （重量％）が（１）式で定義された上限を超えると、紡出糸条の冷却効果は高いものの、製糸性が低下するとともに得られた長繊維ひいては不織布の機械的性能が劣り好ましくない。逆に、結晶核剤の全添加量ＱＡ ＋ＱＢ （重量％）が（１）式で定義された下限より低くなると、紡出糸条の冷却性が低下して紡出糸条間に密着が発生し、目標とする不織布を得ることが困難となる。また、高融点成分中への結晶核剤の添加量ＱＡ （重量％）が、低融点成分中への結晶核剤の添加量ＱＢ （重量％）よりも多くなると、高融点成分の冷却性はさらに向上するが、低融点成分の冷却性が低くなり、これによって紡出糸条間に密着が発生しやすくなるため好ましくない。
【００２６】
ところで、（１）式において、ΔＴは各成分の融点と結晶化温度との差であるが、製糸工程においては、このΔＴが小さいほうが紡出糸条の冷却性は向上する。本発明の重合体において、ΔＴは通常３５以上と大きくなるが、結晶核剤を添加することにより効果的に紡出糸条の冷却を促進することができるのである。
【００２７】
なお、本発明においては高融点成分または低融点成分に、あるいは両成分ともに、必要に応じて、例えば艶消し剤、顔料、光安定剤、耐候剤、酸化防止剤などの各種添加剤を本発明の効果を損なわない範囲内で添加することができる。
【００２８】
次に、本発明に適用される複合長繊維の繊維横断面形状について説明する。
本発明の多葉型複合断面においては、低融点成分が芯部を形成し、高融点成分が前記低融点成分の円周方向に独立した突起部を複数形成し、しかも前記低融点成分は高融点成分によって分断されることなく連続しており、高融点成分および低融点成分はともに繊維軸方向に連続するとともに繊維表面において交互に露出していることが必要である。さらに詳しくは、高融点成分が芯部を形成する低融点成分の円周方向に個々に独立した突起部を複数形成していること、すなわち低融点成分が高融点成分によって分断されることなく連続していることは、優れた生分解性能を維持させるのに必要である。また、高融点成分および低融点成分のいずれもが繊維軸方向に連続することは、繊維横断面の安定性、製糸性および繊維の機械的特性を向上させるために必要である。さらに、高融点成分および低融点成分が繊維表面において交互に露出していることは、紡出糸条の冷却性、開繊性の向上および生分解性能の促進、制御のために必要である。
【００２９】
このような繊維横断面形状を有する長繊維を適用することにより、たとえば低融点成分が冷却性および開繊性に劣る重合体であっても、突起部に配設する高融点成分により糸条間の凝集が防止され紡出糸条の冷却性および開繊性を向上させることができる。また、高融点成分が生分解性能に劣る重合体であっても、芯部に配設された低融点成分の生分解性能が優れるため、経時的に高融点成分が小片として取り残される状態となり、この小片の繊度が極めて細いことから、不織布としての生分解性能には優れる結果となるのである。
【００３０】
本発明に適用される複合長繊維の繊維横断面において、高融点成分の突起部数は４〜１０であることが好ましい。高融点成分の突起部数が４未満であると、紡出糸条の冷却性、開繊性および生分解性能に劣ることとなる。すなわち、本発明においては高融点成分の円周方向に占める割合が大きいほど、紡出糸条の冷却性および開繊性には優れる結果となるが、突起部数が４未満であると、低融点成分の円周占有率が大きくなり冷却性および開繊性に劣ることとなる。これを回避するために高融点成分の複合比を上げると、個々に独立した高融点成分のセグメント繊度、すなわち繊維横断面において高融点成分が占める最小構成単位部分の繊度が大きくなるのであるから、必然的に不織布の生分解性能には劣ることとなる。逆に、高融点成分の突起部数が１０を超えると、高融点成分の各セグメントを個々に独立させることが困難となり好ましくない。これらの理由により、高融点成分の突起部数は、さらに好ましくは、５〜１０が良い。
【００３１】
また、本発明に適用される複合長繊維の繊維横断面における高融点成分／低融点成分の周長比、すなわち繊維横断面の外周において各成分の占める周長合計の比は、高融点成分／低融点成分が９０／１０〜４０／６０であることが好ましい。たとえば、繊維横断面の外周における高融点成分の円周占有率が大きくなると、それにつれて突起部分が大きくなり、ウエブを熱圧接する際の低融点成分の円周占有率が小さすぎるため圧接されにくく機械的性能に劣る不織布しか得られないこととなる。しかも、個々に独立した高融点成分のセグメント繊度も大きくなることから、不織布の生分解性能も低下する傾向になる。逆に、繊維横断面の外周における低融点成分の円周占有率が大きくなると、紡出糸条が冷却性されにくくなり、延伸・開繊工程において融着を生じやすくなる。
【００３２】
本発明に適用される複合長繊維の繊維横断面において、個々に独立した高融点成分のセグメントの配設形態は、前記の繊維横断面形状を満足するものであれば制限はないが、高融点成分の各セグメントが繊維横断面の外周上に各々等間隔に位置していることが好ましい。高融点成分の各セグメントが繊維横断面の外周上に各々片寄りをもって位置する場合においては、紡糸工程において紡出糸条がニーリングを発生するとともに、ウエブを熱圧接する際に繊維同士が絡合しにくく、高融点成分と低融点成分との接着点が均一に付与できず、不織布の強力にムラが生じやすくなる。さらに、高融点成分の各セグメントは、全て同じ割合で低融点成分のなかに埋没するように配設されていることが好ましい。高融点成分の各セグメントが各々異なる割合で低融点成分のなかに埋没するような場合においては、ウエブを熱圧接する際に繊維同士が絡合しにくく、高融点成分と低融点成分との接着点が均一に付与できないため、不織布の強力にムラが生じやすくなる。また、高融点成分の各セグメントがどのような割合で低融点成分のなかに埋没するように配設されているかについては、たとえば、図１に示すように、高融点成分１の各セグメントの中心３が低融点成分２の円周より外側にあるような配設形態、すなわち高融点成分１の円周占有率が大きい場合から、図２に示すように、高融点成分１の各セグメントの中心３が低融点成分２の円周より内側にあるような配設形態、すなわち低融点成分２の円周占有率が大きい場合まで、任意の形態を適用できるが、少なくとも、高融点成分１の各セグメントが製糸・製反工程において剥離しない程度に低融点成分２と重なり合っていること、ならびに低融点成分２が内部に埋没した高融点成分１によって分断されていないことが必要である。ウエブを熱圧接する際の繊維同士の絡合しやすさからは、たとえば、図３に示すように、高融点成分１の各セグメントの中心３が低融点成分２の円周上にあるような配設形態が良い。
【００３３】
本発明に適用される複合長繊維の高融点成分／低融点成分の複合比は１／３〜３／１（重量比）であることが好ましい。複合比がこの範囲を外れると紡出糸条の冷却性、開繊性および生分解性能の全てを併せて満足することができず、さらに、繊維横断面形状の不安定さを誘発するため好ましくない。たとえば、高融点成分／低融点成分の複合比が１／３を超えると、生分解性能には優れるものの、紡出糸条の冷却性、開繊性には劣る結果となる。逆に、高融点成分／低融点成分の複合比が３／１を超えると、紡出糸条の冷却性、開繊性には優れるものの、生分解性能には劣る結果となる。たとえば、高融点成分が生分解性能に劣る重合体であれば、低融点成分の複合比を上げることにより生分解速度を促進させることができる。この理由により、高融点成分／低融点成分の複合比は、さらに好ましくは１／２〜２／１（重量比）が良い。
【００３４】
本発明に適用される複合長繊維の高融点成分の各セグメント繊度は０．０５〜２デニールであることが好ましい。ここで、高融点成分のセグメント繊度とは、繊維横断面において高融点成分が占める最小構成単位部分の繊度のことである。高融点成分の各セグメント繊度が０．０５デニール未満であると、生産量の低下および繊維横断面形状の不安定さなどにより好ましくない。逆に、高融点成分の各セグメント繊度が２デニールを超えると、紡出糸条の冷却性、開繊性に劣るとともに生分解性能にも劣る結果となる。これらの理由により、高融点成分の各セグメント繊度は、さらに好ましくは０．１〜１デニールが良い。
【００３５】
また、高融点成分の各セグメント繊度と同様に、本発明に適用される複合長繊維の単糸繊度は１．５〜１０デニールであること好ましい。単糸繊度が１．５デニール未満であると、紡糸口金の複雑化、製糸工程における糸切れの増大、生産量の低下および繊維断面形状の不安定化などにより好ましくない。逆に、１０デニールを超えると、紡出糸条の冷却性に劣るとともに生分解性能にも劣ることとなる。これらの理由により、単糸繊度は、さらに好ましくは２〜８デニールが良い。
【００３６】
次に、本発明の生分解性不織布のうち、前記の長繊維不織ウエブに天然繊維不織ウエブを積層して超音波融着により一体化された積層不織布について説明する。
【００３７】
本発明に適用される天然繊維は、生分解性を有するものであれば特に制限はないが、特に、コットン、ラミー、短繊維状に裁断されたシルク繊維等が好適に用いられる。ここで、コットンとしては、晒し加工の施されていないコーマ糸、晒し加工の施された晒し綿、または織物・編み物から得られた反毛等が挙げられる。
【００３８】
本発明における天然繊維不織ウエブは、前記天然繊維を単独または複数組み合わせて作成されるウエブであり、カード機の進行方向に配列したパラレルウエブ、パラレルウエブのクロスレイドされたウエブ、ランダムに配列したランダムウエブあるいは中程度に配列したセミランダムウエブのいずれであっても良く、使用用途によって適宜選択することができる。特に、衣料用途に用いる場合には、不織布としての強力において、縦／横強力比が概ね１／１となるカードウエブを使用するのが好ましい。
【００３９】
天然繊維不織ウエブを積層する場合、天然繊維不織ウエブと長繊維不織ウエブとの積層比率は１０／９０〜９０／１０（重量％）であることが好ましい。天然繊維が１０重量％未満であると、積層不織布の機械的特性には優れるものの、吸湿性、吸水性を充分に向上させることができず、天然繊維を積層した目的を達成することができないため好ましくない。逆に、天然繊維が９０重量％を超えると、吸湿性、吸水性には優れるものの、機械的特性を損なうこととなり好ましくない。これらの理由により、天然繊維不織ウエブと長繊維不織ウエブとの積層比率は２０／８０〜８０／２０（重量％）であることがさらに好ましい。
【００４０】
積層された長繊維不織ウエブと天然繊維不織ウエブとの一体化は、超音波融着処理によって行われる。この超音波融着処理は後述の超音波融着装置を用いて部分的な融着区域を形成するものであり、融着区域における複合長繊維を熱融解させて天然繊維の内部に埋没させることにより、長繊維不織ウエブと天然繊維不織ウエブとが融着される。これにより、長繊維不織ウエブと熱接着性を有しない天然繊維とを実用に耐えうるだけの接着力で一体化することができる。
【００４１】
以上のように、本発明の生分解性不織布は、生分解性能を異にする高融点成分および低融点成分で構成された多葉型複合長繊維よりなる不織布であって、両成分の複合比、高融点成分の突起部数、高融点成分の各セグメント繊度、単糸繊度などを組み合わせることにより、要求する紡出糸条の冷却性、開繊性、生分解性能を制御することができるのである。
【００４２】
次に、本発明の生分解性不織布の製造方法について説明する。
まず、本発明の生分解性不織布のうち、長繊維不織ウエブが部分的に熱圧接されて所定の形態を保持してなる長繊維不織布についての製造方法を説明する。
【００４３】
本発明の生分解性不織布の製造は、通常の複合紡糸装置を用いて行なうことができる。まず、前述したところの高融点成分のＭＦＲ値が１５〜５０ｇ／１０分、低融点成分のＭＦＲ値が２０〜７０ｇ／１０分である生分解性を有する脂肪族ポリエステル、すなわち高融点成分としてポリブチレンサクシネートあるいはブチレンサクシネートの共重合量比が８０モル％以上であるブチレンサクシネートを主繰り返し単位とした共重合ポリエステルを、低融点成分としてブチレンサクシネートの共重合量比が７０〜９０モル％であるブチレンサクシネートを主繰り返し単位とした共重合ポリエステルを好適材料として用い、これらを別々に溶融し、高融点成分／低融点成分の複合比が１／３〜３／１（重量比）となるように個別に計量した後、前述の高融点成分の突起部数、高融点成分の各セグメント繊度、単糸繊度を満足する繊維横断面構造を形成可能な多葉型複合紡糸口金より吐出した紡出糸条を冷却空気流などを用いた公知の冷却装置にて冷却する。次いで、エアーサッカーなどの引取手段を用いて目標繊度となるよう牽引細化して引き取られる。牽引細化した複合長繊維は公知の開繊器具にて開繊せしめた後、スクリーンコンベアなどの移動式捕集面上に開繊堆積させて長不織ウエブとする。その後、この長繊維不織ウエブを熱圧接装置を用い部分的に熱圧接して生分解性不織布が得られるのである。
【００４４】
本発明の生分解性不織布の製造方法においては、用いる重合体、特に低融点成分を構成する重合体に前述の結晶核剤を添加することにより、紡出糸条の密着を防止し、冷却性、開繊性を向上させることができる。
【００４５】
溶融紡糸において、紡糸温度は、用いる脂肪族ポリエステルによって異なるものの、少なくとも重合体のＭＦＲ値と繊維形成性すなわち製糸性とを勘案すれば適宜設定することができる。通常は、紡糸温度を重合体の融点より少なくとも４０℃高い温度とし、特に１２０〜３００℃とするのが好ましい。紡糸温度が１２０℃未満であると、重合体の未溶融物が発生したり、溶融粘度が高過ぎるため溶融押出機を用いて重合体を押出すことが困難となり、逆に、紡糸温度が３００℃を超えると、重合体が熱分解をし始めるため、いずれも好ましくない。
【００４６】
牽引速度は２０００ｍ／分以上であることが必要であり，特に２５００ｍ／分以上とすると不織布の寸法安定性が向上するためさらに好適である。牽引速度が２０００ｍ／分未満であると、紡出糸条の冷却性、可紡性および開繊性に劣り、さらに得られる不織布の機械的性能および寸法安定性に劣ることとなるため好ましくない。
【００４７】
長繊維不織ウエブに部分的な熱圧接処理を施すに際しては、加熱されたエンボスロールと表面が平滑な金属ロールとを用いて長繊維間に点状融着区域を形成する方法、あるいは超音波融着装置を用いパターンロール上で超音波による高周波を印加してパターン部の長繊維間に点状融着区域を形成する方法が採用される。
【００４８】
前記部分的な熱圧接とは、構成繊維間において、低融点成分と高融点成分とが熱圧接されることでウエブの形態を保持し、少なくとも高融点成分同士は融着されず構成繊維同士の完全融着を防止し得るような熱圧接をいい、このような部分的熱圧接とすることにより、所定の不織布形態を保持しつつ生分解性能および柔軟性を発揮させることができる。
【００４９】
部分的熱圧接により形成された圧接領域は、長繊維不織ウエブの全表面積に対して特定の領域を有するものであり、具体的には、個々の熱圧接領域は丸型，楕円型，菱型，三角型，Ｔ字型，井型など任意の形状であって良いが、０．０７〜１．５ｍｍ２ の面積を有し、その密度すなわち圧接点密度が１０〜１２０点／ｃｍ２ 、好ましくは２０〜６０点／ｃｍ２ であるのが良い。圧接点密度が１０点／ｃｍ２ 未満であると得られる不織布の機械的特性や寸法安定性が向上せず、逆に、圧接点密度が１２０点／ｃｍ２ を超えると柔軟性と嵩高性が向上せず、いずれも好ましくない。また、ウエブの全表面積に対する全熱圧接領域の面積の比すなわち圧接面積率は３〜４０％好ましくは４〜３０％であるのが良い。この圧接面積率が３％未満であると得られる不織布の寸法安定性に劣り好ましくない。逆に、圧接面積率が４０％を超えると、得られた不織布の柔軟性および嵩高性を損なうとともに、生分解性能にも劣ることとなるため好ましくない。
【００５０】
加熱されたエンボスロールを用いる場合、ロールの表面温度すなわち加工温度は低融点成分の融点以下の温度としなければならない。低融点成分の融点を超えると、熱圧接装置に重合体が固着し操業性を著しく損なうばかりか、不織布の風合いが硬くなり柔軟な不織布が得られないこととなる。
【００５１】
超音波融着装置を用いる場合、周波数が約２０ｋＨｚの通常ホーンと呼称される超音波発振器と、円周上に点状または帯状に凸状突起部を具備するパターンロールとからなる装置が採用される。前記超音波発振器の下部に前記パターンロールが配設され、長繊維不織ウエブを超音波発振器とパターンロールとの間に通すことにより部分的に熱融着することができる。このパターンロールに配設される凸状突起部１列あるいは複数列であってもよく、また、その配設が複数列の場合には、並列あるいは千鳥型のいずれの配列でも良い。
【００５２】
なお、部分的な熱圧接処理は、連続工程あるいは別工程のいずれで行っても良い。また、熱圧接処理については、前述の加熱されたエンボスロールあるいは超音波融着装置のいずれを選択しても良いが、不織布の使用用途に応じ、特に柔軟性が要求される医療・衛生材料や拭き取り布などの一般生活関連材としては、超音波融着装置を用いると、優れた性能を有する不織布を得ることができる。
【００５３】
次に、本発明の生分解性不織布のうち、長繊維不織ウエブと天然繊維不織ウエブとを積層した積層不織布を得る方法について説明する。
前記と同様にして移動式補集面上に開繊堆積させた長繊維不織ウエブに、常法により別途作成した天然繊維を積層し、これに超音波融着処理を施して一体化させて積層不織布を得る。
【００５４】
超音波融着処理を施すに際しては、前述の部分的熱圧接処理の場合と同様の超音波融着装置が好適に用いられる。詳しくは、ロールの加圧には空気圧が使用され、ホーンがロールに接する線圧は１．０〜５０ｋｇ／ｃｍの範囲とすることが好ましい。線圧が１．０ｋｇ／ｃｍ未満であると、積層不織布の厚みに対し押し圧が不足となり積層体の剥離強力が小さくなり好ましくない。逆に、線圧が５０ｋｇ／ｃｍを超えると、融着部分に対して圧力が掛かり過ぎるため、融着部分のフイルム化により同様に接着強力の低下を招き好ましくない。
【００５５】
本発明においては、移動式補集面上に開繊堆積させた長繊維不織ウエブと天然繊維不織ウエブとを積層する前に予め、長繊維不織ウエブに仮熱圧接処理または熱風接着処理または三次元交絡処理を公知の方法により施しておくことが好ましい。これにより、長繊維不織ウエブと天然繊維不織ウエブとを積層する際に、長繊維織ウエブの形態を予備的に保持することができる。
【００５６】
本発明の生分解性不織布の目付けは、使用目的により選択されるため特に限定されるものではないが、一般的には１０〜１５０ｇ／ｍ２ の範囲が好ましく、より好ましくは１５〜７０ｇ／ｍ２ の範囲である。目付けが１０ｇ／ｍ２ 未満では柔軟性および生分解速度には優れるものの機械的強力に劣り実用的ではない。逆に、目付けが１５０ｇ／ｍ２ を超えると、不織布が硬い風合いのものとなり、柔軟性に劣るものとなる。
【００５７】
【実施例】
次に、実施例に基づき本発明を具体的に説明するが、本発明は、これらの実施例によって何ら限定されるものではない。
【００５８】
実施例において、各物性値の測定を次の方法により実施した。
・メルトフローレート値（ｇ／１０分）；ＡＳＴＭ−Ｄ−１２３８（Ｅ）に記載の方法に準じて温度１９０℃で測定した。（以降、ＭＦＲ値と記す）
【００５９】
・融点（℃）；パーキンエルマ社製示差走査型熱量計ＤＳＣ−２型を用い、試料重量を５ｍｇ、昇温速度を２０℃／分として測定して得た融解吸熱曲線の最大値を与える温度を融点（℃）とした。
【００６０】
・結晶化温度（℃）；パーキンエルマ社製示差走査型熱量計ＤＳＣ−２型を用い、試料重量を５ｍｇ、昇温速度を２０℃／分として測定して得た固化発熱曲線の最大値を与える温度を結晶化温度（℃）とした。
【００６１】
・冷却性；紡出糸条を目視して下記の４段階にて評価した。
◎；密着糸が認められない。
○；密着糸がわずかではあるが認められる。
△；密着糸があり、繊維が一部集束している。
×；大部分が密着し、開繊不可能である。
【００６２】
・開繊性；開繊器具より吐出した紡出糸条にて形成された長繊維不織ウエブを、目視にて下記の４段階にて評価した。
◎；構成繊維が分繊され、密着糸および収束糸が全く認められない。
○；密着糸および収束糸がわずかではあるが認められる。
△；密着糸および収束糸があり、開繊性がやや不良である。
×；構成繊維の大部分が密着し、開繊性が不良である。
【００６３】
・目付け（ｇ／ｍ２ ）；標準状態の試料から試料長が１０ｃｍ、試料幅が１０ｃｍの試料片１０点を作成し平衡水分にした後、各試料片の重量（ｇ）を秤量し、得られた値の平均値を単位面積当たりに換算し、目付け（ｇ／ｍ２ ）とした。
【００６４】
・不織布の強力（ｋｇ／５ｃｍ幅）；ＪＩＳ−Ｌ−１０９６Ａに記載の方法に準じて測定した。すなわち、試料長が２０ｃｍ、試料幅が５ｃｍの試料片１０点を作成し、試料片毎に不織布の縦方向について、定速伸張型引張り試験機（東洋ボールドウイン社製テンシロンＵＴＭ−４−１−１００）を用いて、引張り速度１０ｃｍ／分で伸張し、得られた切断時荷重値の平均値を強力（ｋｇ／５ｃｍ幅）とした。
【００６５】
・不織布の圧縮剛軟度（ｇ）；試料長が１０ｃｍ、試料幅が５ｃｍの試料片５点を作成し、各試料片毎に横方向に曲げて円筒状物とし、各々その端部を接合したものを圧縮剛軟度測定試料とした。次いで、各測定試料毎にその軸方向について、定速伸長型引長試験機（東洋ボールドウイン社製テンシロンＵＴＭ−４−１−１００）を用い、圧縮速度５ｃｍ／分で圧縮し、得られた最大荷重値（ｇ）の平均値を圧縮剛軟度（ｇ）とした。なお、この圧縮剛軟度とは、値が小さいほど柔軟性が優れることを意味するものである。
【００６６】
・生分解性能；不織布を土中に埋設し、６ヶ月後に取り出し、不織布がその形態を保持していない場合、あるいは、その形態を保持していても強力が埋設前の強力初期値に対して５０％以下に低下している場合、生分解性能が良好（；○）であるとし、強力が埋設前の強力初期値に対して７５％以下に低下している場合、生分解性能は普通（；△）であるとし、強力が埋設前の強力初期値に対して７５％を超える場合、生分解性能が不良（；×）であると評価した。
【００６７】
・層間剥離強力（ｇ／５ｃｍ幅）：試料長が１５ｃｍ、試料幅が５ｃｍの試料片計３点を準備し、各試料毎に不織布の経方向について、定速伸張型引張試験機（東洋ボールウィン社製テンシロンＵＴＭ−４−−１−１００）を用いて、積層不織布における、長繊維不織ウエブの端部と天然繊維不織ウエブの端部とを上下チャックにて把持し、剥離速度５ｃｍ／分にて５ｃｍ長を強制的に剥離させて得られた荷重値の平均値を層間剥離を（ｇ／５ｃｍ幅）とした。
【００６８】
・吸水性（ｍｍ）：ＪＩＳ−Ｌ−１０９６に記載のバイレック法に準じて測定した。すなわち、試料長が２０ｃｍ、試料幅が２．５ｃｍの試料片５点を作成し、各試料片を２０±２℃の水を入れた水槽上の一定の高さに支えた水平棒上にピンで留めて吊す。試料片の下端を一線に並べて水平棒を下げ、試料片の下端の１ｃｍがちょうど水に浸かるようにする。１０分間放置後の水の上昇した高さ（ｍｍ）を測り、その平均値を吸水性（ｍｍ）とした。
【００６９】
実施例１
高融点成分として、ＭＦＲ値が２０ｇ／１０分で融点１１４℃、結晶化温度７５℃のポリブチレンサクシネートを、低融点成分として、ＭＦＲ値が３０ｇ／１０分で融点１０２℃、結晶化温度５２℃のブチレンサクシネート／エチレンサクシネート＝８５／１５（モル％）の共重合ポリエステルを用いて、多葉型複合長繊維よりなる不織布を製造した。
【００７０】
すなわち、前記２成分を、高融点成分／低融点成分の複合比が１／１（重量比）となるように個別に計量した後、個別のエクストルーダ型溶融押出し機を用いて温度１８０℃で溶融し、図３に示すような高融点成分配列形態の繊維横断面（高融点成分突起部数＝６）となる紡糸口金を用い、単孔吐出量１．９ｇ／分で多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、口金の下方に設置したエアーサッカーを用いて、牽引速度が４２００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．１デニール（高融点成分セグメント繊度＝０．３４デニール×６、低融点成分セグメント繊度＝２．０デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件としては、面積が０．６ｍｍ２ の彫刻模様で圧接点密度が２０点／ｃｍ２ 、圧接面積率が１５％で配設された熱エンボスロールと表面が平滑な金属ロールとを用い、加工温度を９５℃とした。操業性および不織布物性、生分解性能を表１に示す。
【００７１】
実施例２
低融点成分としてＭＦＲ値が３０ｇ／１０分で融点１０５℃、結晶化温度２９℃のブチレンサクシネート／ブチレンアジペート＝８０／２０（モル％）の共重合ポリエステルを用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が３９００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．４デニール（高融点成分セグメント繊度＝０．３７デニール×６、低融点成分セグメント繊度＝２．２デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、加工温度を９８℃とすること以外は実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表１に示す。
【００７２】
実施例３
低融点成分としてＭＦＲ値が３０ｇ／１０分で融点１０５℃、結晶化温度３２℃のブチレンサクシネート／ブチレンセバケート＝８５／１５（モル％）の共重合ポリエステルを用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が３８００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．５デニール（高融点成分セグメント繊度＝０．３８デニール×６、低融点成分セグメント繊度＝２．３デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、加工温度を９８℃とすること以外は実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表１に示す。
【００７３】
実施例４
高融点成分としてＭＦＲ値が２０ｇ／１０分で融点９６℃、結晶化温度４０℃のブチレンサクシネート／エチレンサクシネート＝８０／２０（モル％）の共重合ポリエステルを用い、低融点成分としてＭＦＲ値が３０ｇ／１０分で融点９０℃、結晶化温度２５℃のブチレンサクシネート／エチレンサクシネート＝７０／３０（モル％）の共重合ポリエステルを用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が３７００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．６デニール（高融点成分セグメント繊度＝０．３９デニール×６、低融点成分セグメント繊度＝２．３デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、加工温度を８３℃とすること以外は実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表１に示す。
【００７４】
実施例５
低融点成分としてＭＦＲ値が３０ｇ／１０分で融点１０８℃、結晶化温度６８℃のブチレンサクシネート／エチレンサクシネート＝９５／５（モル％）の共重合ポリエステルを用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が４２００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．１デニール（高融点成分セグメント繊度＝０．３４デニール×６、低融点成分セグメント繊度＝２．０デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２の生分解性不織布を得た。熱圧接条件は、加工温度を１００℃とした以外は実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表１に示す。
【００７５】
実施例６
高融点成分としてＭＦＲ値が２０ｇ／１０分で融点１１０℃、結晶化温度５２℃のブチレンサクシネート／ブチレンアジペート＝９０／１０（モル％）の共重合ポリエステルを用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が３５００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．９デニール（高融点成分セグメント繊度＝０．４１デニール×６、低融点成分セグメント繊度＝２．４デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表２に示す。
【００７６】
実施例７
高融点成分としてＭＦＲ値が２０ｇ／１０分で融点１１０℃、結晶化温度５４℃のブチレンサクシネート／ブチレンセバケート＝９０／１０（モル％）の共重合ポリエステルを用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が３４００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度５．０デニール（高融点成分セグメント繊度＝０．４２デニール×６、低融点成分セグメント繊度＝２．５デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表２に示す。
【００７７】
実施例８
高融点成分としてＭＦＲ値が１２ｇ／１０分で融点１７８℃、結晶化温度１０３℃のポリ−Ｌ−乳酸を用い、低融点成分としてＭＦＲ値が３５ｇ／１０分で融点１５４℃、結晶化温度２８℃のＬ−乳酸／ε−カプロラクトン＝８５／１５（モル％）の共重合ポリエステルを用い、紡糸温度を２４０℃とすること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が３８００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．５デニール（高融点成分セグメント繊度＝０．３８デニール×６、低融点成分セグメント繊度＝２．３デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、加工温度を１４７℃とすること以外は実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表２に示す。
【００７８】
実施例９
低融点成分としてＭＦＲ値が３０ｇ／１０分で融点９２℃、結晶化温度２０℃のブチレンサクシネート／エチレンサクシネート＝７０／３０（モル％）の共重合ポリエステルを用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が３９００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．４デニール（高融点成分セグメント繊度＝０．３７デニール×６、低融点成分セグメント繊度＝２．２デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、加工温度を８５℃とすること以外は実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表２に示す。
【００７９】
実施例１０
低融点成分としてＭＦＲ値が３０ｇ／１０分で融点１０８℃、結晶化温度５７℃のブチレンサクシネート／エチレンサクシネート＝９０／１０（モル％）の共重合ポリエステルを用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が４２００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．１デニール（高融点成分セグメント繊度＝０．３４デニール×６、低融点成分セグメント繊度＝２．０デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、加工温度を１０１℃とすること以外は実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表２に示す。
【００８０】
実施例１１
高融点成分として、ＭＦＲ値が５ｇ／１０分で融点１１４℃、結晶化温度７５℃のポリブチレンサクシネートを用い、低融点成分として、ＭＦＲ値が１０ｇ／１０分で融点１０２℃、結晶化温度５２℃のブチレンサクシネート／エチレンサクシネート＝８５／１５（モル％）の共重合ポリエステルを用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が３５００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．９デニール（高融点成分セグメント繊度＝０．４１デニール×６、低融点成分セグメント繊度＝２．５デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表２に示す。
【００８１】
実施例１２
高融点成分として、ＭＦＲ値が５０ｇ／１０分で融点１１４℃、結晶化温度７５℃のポリブチレンサクシネートを用い、低融点成分としてＭＦＲ値が６０ｇ／１０分で融点１０２℃、結晶化温度５２℃のブチレンサクシネート／エチレンサクシネート＝８５／１５（モル％）の共重合ポリエステルを用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が４５００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度３．８デニール（高融点成分セグメント繊度＝０．３２デニール×６、低融点成分セグメント繊度＝１．９デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表２に示す。
【００８２】
実施例１３
実施例１と同一の２成分を原料とし、図１に示すような高融点成分配列形態の繊維横断面（高融点成分突起部数＝６）となる紡糸口金を用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて牽引速度が３８００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．５デニール（高融点成分セグメント繊度＝０．３８デニール×６、低融点成分セグメント繊度＝２．３デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例と同一条件で実施した。操業性および不織布物性、生分解性能を表３に示す。
【００８３】
実施例１４
実施例１と同一の２成分を原料とし、高融点成分の突起部数が４であり、かつ図３と同様の配設形態を有する繊維横断面となるような紡糸口金を用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて牽引速度が４０００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．３デニール（高融点成分セグメント繊度＝０．５３デニール×４、低融点成分セグメント繊度＝２．１デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例と同一条件で実施した。操業性および不織布物性、生分解性能を表３に示す。
【００８４】
実施例１５
実施例１と同一の２成分を原料とし、高融点成分の突起部数が１０であり、かつ図３と同様の配設形態を有する繊維横断面となるような紡糸口金を用いること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて牽引速度が４３００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．０デニール（高融点成分セグメント繊度＝０．２０デニール×１０、低融点成分セグメント繊度＝２．０デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例と同一条件で実施した。操業性および不織布物性、生分解性能を表３に示す。
【００８５】
実施例１６
実施例１と同一の２成分を原料とし、高融点成分／低融点成分の複合比が１／３（重量比）となるように個別に計量した後、単孔吐出量を２．０ｇ／分とすること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて牽引速度が４０００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．５デニール（高融点成分セグメント繊度＝０．１９デニール×６、低融点成分セグメント繊度＝３．４デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例と同一条件で実施した。操業性および不織布物性、生分解性能を表３に示す。
【００８６】
実施例１７
実施例１と同一の２成分を原料とし、高融点成分／低融点成分の複合比が３／１（重量比）となるように個別に計量した後、単孔吐出量を２．０ｇ／分とすること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が４４００ｍ／分で牽引細化して引き取った。次いで公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．１デニール（高融点成分セグメント繊度＝０．５１デニール×６、低融点成分セグメント繊度＝１．０デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表３に示す。
【００８７】
実施例１８
実施例１と同一の２成分を原料とし、高融点成分／低融点成分の複合比が１／４（重量比）となるように個別に計量した後、単孔吐出量を２．０ｇ／分とすること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて牽引速度が３３００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度５．５デニール（高融点成分セグメント繊度＝０．１８デニール×６、低融点成分セグメント繊度＝４．４デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。操業性を表３に示す。
【００８８】
実施例１９
実施例１と同一の２成分を原料とし、高融点成分／低融点成分の複合比が４／１（重量比）となるように個別に計量した後、単孔吐出量を２．０ｇ／分とすること以外は実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて牽引速度が４４００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．１デニール（高融点成分セグメント繊度＝０．５５デニール×６、低融点成分セグメント繊度＝０．８デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表３に示す。
【００８９】
実施例２０
実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が２０００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度８．６デニール（高融点成分セグメント繊度＝０．７１デニール×６、低融点成分セグメント繊度＝４．３デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表４に示す。
【００９０】
実施例２１
実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出、次いで、牽引細化、開繊し、単糸繊度４．１デニール（高融点成分セグメント繊度＝０．３４デニール×６、低融点成分セグメント繊度＝２．０デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを超音波融着装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、面積が０．６ｍｍ２ の彫刻模様で圧接点密度が２０点／ｃｍ２、圧接面積率が１５％で配設されたロールを用い、周波数を１９．５ｋＨｚとした。操業性および不織布物性、生分解性能を表４に示す。
【００９１】
実施例２２
実施例１と同一条件下にて、多葉型複合長繊維を溶融紡出、次いで牽引細化、開繊し、単糸繊度４．１デニール（高融点成分セグメント繊度＝０．３４デニール×６、低融点成分セグメント繊度＝２．０デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、加工温度を９８℃とした以外は実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表４に示す。
【００９２】
実施例２３
多葉型複合長繊維からなる長繊維不織ウエブを得、これに天然繊維からなる不織ウエブを積層した積層不織布を得た。すなわち、実施例１と同一条件下にて、移動式補集面上に開繊堆積させた長繊維不織ウエブに、予めエンボスロールからなる熱圧接装置にて仮熱圧接を施した。熱圧接条件としては、面積が０．６ｍｍ２ の彫刻模様で圧接点密度が２０点／ｃｍ２ 、圧接面積率が１５％で配設された熱エンボスロールと表面が平滑な金属ロールとを用い、加工温度を５５℃とした。一方、天然繊維からなる不織ウエブとして、木綿の晒し綿を用い、ランダムカ−ド機により目付けが２５ｇ／ｍ２ のカードウエブを作成した。
【００９３】
次いで、仮熱圧接処理を施した前述の長繊維不織ウエブに晒し綿よりなる天然繊維不織ウエブを積層し、超音波融着装置にて融着処理を施し、目付けが５０ｇ／ｍ２ の積層不織布を得た。融着処理条件としては、周波数１９．７ｋＨｚ、面積が０．４ｃｍ２ の彫刻模様が施されたロ−ルには凸部が配設され、凸部の圧接面積率１５％、線圧２．０ｋｇ／ｃｍで実施した。操業性および不織布物性、生分解性能を表５に示す。
【００９４】
実施例２４
実施例２３と同一の長繊維不織ウエブおよび天然繊維不織ウエブを用い、長繊維不織ウエブの目付けを１０ｇ／ｍ２ とし、天然繊維不織ウエブの目付けを４０ｇ／ｍ２ としたこと以外、実施例２３と同一条件下にて目付けが５０ｇ／ｍ２ の積層不織布を得た。操業性および不織布物性、生分解性能を表５に示す。
【００９５】
実施例２５
実施例２３と同一の長繊維不織ウエブおよび天然繊維不織ウエブを用い、長繊維不織ウエブの目付けを４０ｇ／ｍ２ とし、天然繊維不織ウエブの目付けを１０ｇ／ｍ２ としたこと以外、実施例２３と同一条件下にて目付けが５０ｇ／ｍ２ の積層不織布を得た。操業性および不織布物性、生分解性能を表５に示す。
【００９６】
実施例２６
高融点成分重合体として、ＭＦＲ値が４０ｇ／１０分で、融点１１４℃、結晶化温度７５℃のポリブチレンサクシネート（ＰＢＳ）を用い、低融点成分重合体として、ＭＦＲ値が３０ｇ／１０分で、融点１０２℃、結晶化温度５２℃のブチレンサクシネート／エチレンサクシネート（ＢＳ／ＥＳ）＝８５／１５（モル％）の共重合体を用いた。一方、結晶核剤として、平均粒径が１．０μｍのタルク／酸化チタン＝１／１（重量比）を２０重量％含有させたマスターバッチを高融点成分重合体および低融点成分重合体ベースであらかじめ作成し、このマスターバッチとそれに対応する重合体とをそれぞれブレンドして、高融点成分に添加する結晶核剤が０．２重量％、低融点成分に添加する結晶核剤が１．０重量％となるようにして原料とした。
【００９７】
この高融点成分と低融点成分とを個別のエクストルーダ型溶融押出し機を用いて紡糸温度１８０℃で溶融し、繊維横断面が図３に示す断面となるような紡糸口金を通して、単孔吐出量１．３５ｇ／分、吐出比が高融点成分／低融点成分＝１／１（重量比）で溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、口金の下方に設置したエアーサッカーを用いて、牽引速度が３５００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に捕集・堆積させて、単糸繊度３．５デニール（高融点成分セグメント繊度＝０．２９デニール×６、低融点成分セグメント繊度＝１．７デニール）の長繊維からなる不織ウエブとした。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して目付けが３０ｇ／ｍ２ の長繊維不織布を得た。熱圧接条件としては、圧接部の形状が丸形で、その面積が０．６８ｍｍ２の彫刻模様でかつ圧接点密度が１６点／ｃｍ２ 、圧接面積率が１５％で配設されたエンボスロールと表面が平滑な金属ロールとを用い、加工温度を９５℃として行った。製造条件、操業性および不織布物性、生分解性能を表６に示す。
【００９８】
実施例２７〜３０
実施例２６における各成分に添加する結晶核剤の添加量を、表６に示すように変更した以外は、実施例２６と同様にして長繊維不織布を得た。製造条件、操業性および不織布物性、生分解性能を表６に示す。
【００９９】
実施例３１
低融点成分としてＭＦＲ値が２０ｇ／１０分で融点８４℃、結晶化温度２０℃のブチレンサクシネート／エチレンサクシネート＝６０／４０（モル％）の共重合ポリエステルを用い、実施例２６と同様にして結晶核剤を添加し、紡糸温度を１６０℃としたこと以外は実施例２６と同一条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が３６００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度３．４デニール（高融点成分セグメント繊度＝０．２８デニール×６、低融点成分セグメント繊度＝１．７デニール）の複合長繊維からなる不織ウエブとして開繊堆積させた。操業性を表７に示す。
【０１０１】
実施例３２
高融点成分重合体として、ＭＦＲ値が３０ｇ／１０分で、融点１０２℃、結晶化温度５２℃のブチレンサクシネート／エチレンサクシネート（ＢＳ／ＥＳ）＝８５／１５（モル％）の共重合体を用い、低融点成分重合体として、ＭＦＲ値が３０ｇ／１０分で、融点６３℃、結晶化温度２３℃のポリカプロラクトンを用いた。一方、結晶核剤として、平均粒径が１．０μｍのタルク／酸化チタン＝１／１（重量比）を１５重量％含有させたマスターバッチを高融点成分重合体および低融点成分重合体ベースであらかじめ作成し、このマスターバッチとそれに対応する重合体とをそれぞれブレンドして、高融点成分に添加する結晶核剤が０．６重量％、低融点成分に添加する結晶核剤が３．０重量％となるようにして原料とした。
【０１０２】
この高融点成分と低融点成分とを個別のエクストルーダ型溶融押出し機を用いて紡糸温度１５０℃で溶融し、繊維横断面が図３に示す断面となるような紡糸口金を通して、単孔吐出量２．００ｇ／分、吐出比が高融点成分／低融点成分＝１．５／１（重量比）で溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、口金の下方に設置したエアーサッカーを用いて、牽引速度が３８００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に捕集・堆積させて、単糸繊度４．７デニール（高融点成分セグメント繊度＝０．４７デニール×６、低融点成分セグメント繊度＝１．９デニール）の長繊維からなる不織ウエブとした。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して目付けが３０ｇ／ｍ２ の長繊維不織布を得た。熱圧接条件としては、圧接部の形状が丸形で、その面積が０．６８ｍｍ２ の彫刻模様でかつ圧接点密度が１６点／ｃｍ２ 、圧接面積率が１５％で配設された熱エンボスロールと表面が平滑な金属ロールとを用い、加工温度を５６℃として行った。製造条件、操業性および不織布物性、生分解性能を表７に示す。
【０１０３】
比較例１
実施例１と同一の高融点成分を単独で用い、繊維横断面が単相型になる紡糸口金を用いること以外は実施例１と同一条件下にて、単相型長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて牽引速度が４３００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．０デニールの長繊維からなる長繊維不織ウエブとして開繊堆積させた。この長繊維不織ウエブを熱エンボスロールからなる熱圧接装置にて熱圧接して、目付けが３０ｇ／ｍ２ の生分解性不織布を得た。熱圧接条件は、加工温度を１０７℃とすること以外は実施例１と同一条件で実施した。操業性および不織布物性、生分解性能を表８に示す。
【０１０４】
比較例２
実施例１と同一の低融点成分を単独で用い、繊維横断面が単相型になる紡糸口金を用いること以外は実施例１と同一条件下にて、単相型長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて牽引速度が４０００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度４．３デニールの長繊維からなる長繊維不織ウエブとして開繊堆積させた。操業性を表８に示す。
【０１０５】
比較例３
実施例１と同一の条件下にて、多葉型複合長繊維を溶融紡出した。この紡出糸条を公知の冷却装置にて冷却した後、エアーサッカーを用いて、牽引速度が１８００ｍ／分で牽引細化して引き取った。次いで、公知の開繊器具にて開繊し、移動するスクリーンコンベア上に単糸繊度９．５デニール（高融点成分セグメント繊度＝０．７９デニール×６、低融点成分セグメント繊度＝４．８デニール）の複合長繊維からなる長繊維不織ウエブとして開繊堆積させた。操業性および不織布物性、生分解性能を表８に示す。
【０１０６】
比較例４
実施例２３と同一の目付けが２５ｇ／ｍ２ の長繊維不織ウエブと目付けが２５ｇ／ｍ２ の晒し綿よりなる天然繊維不織ウエブとを積層し、熱エンボスロールにて熱融着加工を行い、目付けが５０ｇ／ｍ２ の積層不織布を得た。熱融着加工条件としては、ロ−ルには彫刻部面積０．４ｃｍ２ の彫刻模様が施された凸部が配設され、凸部の圧接面積率１５％、線圧５０ｋｇ／ｃｍ、加工温度９５℃で実施した。積層不織布物性、分解性能を表８に示す。
【０１０７】
【表１】
【表２】
【表３】
【表４】
表１、表２、表３および表４から明らかなように、実施例１は、高融点成分としてポリブチレンサクシネートを用い、低融点成分としてブチレンサクシネート／エチレンサクシネート共重合ポリエステルを用いた本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性、および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１１２】
実施例２は、高融点成分としてポリブチレンサクシネートを用い、低融点成分としてブチレンサクシネート／ブチレンアジペート共重合ポリエステルを用いた本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性、および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１１３】
実施例３は、高融点成分としてポリブチレンサクシネートを用い、低融点成分としてブチレンサクシネート／ブチレンセバケート共重合ポリエステルを用いた本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性、および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１１４】
実施例４は、高融点成分および低融点成分としていずれもブチレンサクシネート／エチレンサクシネート共重合ポリエステルを用いた本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性および開繊性も良好であり、機械的特性にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１１５】
実施例５は、低融点成分としてブチレンサクシネート／エチレンサクシネート共重合ポリエステルを用いた本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性および開繊性も良好であった。また、低融点成分のブチレンサクシネートの共重合量比が実施例１よりも高いので、機械的特性には特に優れるものの生分解性能は実施例１よりもやや劣るものであった。
【０１１６】
実施例６は、高融点成分としてブチレンサクシネート／ブチレンアジペート共重合ポリエステルを用い、低融点成分としてブチレンサクシネート／エチレンサクシネート共重合ポリエステルを用いた本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性および開繊性も良好であり、機械的特性にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１１７】
実施例７は、高融点成分としてブチレンサクシネート／ブチレンセバケート共重合ポリエステルを用い、低融点成分としてブチレンサクシネート／エチレンサクシネート共重合ポリエステルを用いた本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性および開繊性も良好であり、機械的特性にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１１８】
実施例８は、高融点成分としてＬ−乳酸を用い、低融点成分としてＬ−乳酸／ε−カプロラクトン共重合ポリエステルを用いた本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性、および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１１９】
実施例９は、低融点成分として用いるブチレンサクシネート／エチレンサクシネート共重合ポリエステルのブチレンサクシネート共重合量比が実施例１よりも低いにもかかわらず、本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性、および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１２０】
実施例１０は、低融点成分として用いるブチレンサクシネート／エチレンサクシネート共重合ポリエステルのブチレンサクシネート共重合量比が実施例１よりも高いにもかかわらず、本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性、および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１２１】
実施例１１は、両成分とも実施例１より高粘度の重合体を用いたにもかかわらず、本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性にやや劣るものの、可紡性および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１２２】
実施例１２は、両成分とも実施例１より低粘度の重合体を用いたにもかかわらず、本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１２３】
実施例１３は、高融点成分の配設形態を図１のように、高融点成分突起部が表面に高く露出するようにしたにもかかわらず、本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性、可紡性、および開繊性も良好であり、実施例１よりも若干強力が劣るものの機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１２４】
実施例１４は、実施例１よりも高融点成分の突起部数を少なくしたため、低融点成分の周長比が大きく、すなわち低融点成分の繊維表面における露出部分が多いにもかかわらず、本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性にやや劣るものの、可紡性および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１２５】
実施例１５は、実施例１よりも高融点成分の突起部数を多くしたため、低融点成分の周長比が小さく、すなわち低融点成分の繊維表面における露出部分が少ないにもかかわらず、本発明の多葉型複合長繊維を適用しているので、得られた不織布の生分解性能には若干劣るものの、紡出糸条の冷却性、可紡性および開繊性も良好であり、機械的性能にも優れるものであった。
【０１２６】
実施例１６は、実施例１よりも低融点成分を多くしたため、低融点成分の周長比が大きく、すなわち低融点成分の繊維表面における露出部分が多いにもかかわらず、本発明の多葉型複合長繊維を適用しているので、紡出糸条の冷却性にやや劣るものの、可紡性および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は実施例１よりも良好な生分解性能を有することが認められた。
【０１２７】
実施例１７は、実施例１よりも低融点成分を少なくしたため、低融点成分の周長比が小さく、すなわち低融点成分の繊維表面における露出部分が少ないにもかかわらず、本発明の多葉型複合長繊維を適用しているので、得られた不織布の生分解性能には若干劣るものの、紡出糸条の冷却性、可紡性および開繊性も良好であり、機械的性能にも優れるものであった。
【０１２８】
実施例１８は、実施例１６よりもさらに低融点成分を多くしたため、低融点成分の周長比が大きく、すなわち低融点成分の繊維表面における露出部分が多くなり、紡出糸条の冷却性に劣り、操業性の面ではあまり好ましくはなかった。
【０１２９】
実施例１９は、実施例１７よりもさらに低融点成分を少なくしたため、低融点成分の周長比が小さく、すなわち低融点成分の繊維表面における露出部分が少なくなるので、得られた不織布の生分解性能には若干劣るものの、紡出糸条の冷却性、可紡性および開繊性も良好であり、機械的性能にも優れるものであった。
【０１３０】
実施例２０は、実施例１よりも紡出糸条の牽引速度を低くしたにもかかわらず、本発明の多葉型複合長繊維を適用しているので、繊度が大きいものの、紡出糸条の冷却性、可紡性および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１３１】
実施例２１は、実施例１で得られた長繊維不織ウエブを、超音波融着装置を用い熱圧接しているので、得られた不織布は柔軟性に優れ、かつ、紡出糸条の冷却性、可紡性、および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１３２】
実施例２２は、実施例１よりも熱圧接工程における加工温度が高くなっているにもかかわらず、本発明の多葉型複合長繊維を適用しているので、得られた不織布は柔軟性に若干劣るものの、紡出糸条の冷却性、可紡性、および開繊性も良好であり、機械的性能にも優れるものであった。また、この不織布は良好な生分解性能を有することが認められた。
【０１３３】
【表５】
表５から明らかなように、実施例２３は、天然繊維からなる不織ウエブを積層した本発明の生分解性不織布であるので、天然繊維により優れた吸水性を具備するとともに、複合長繊維により優れた機械的特性を具備し、かつ複合長繊維が天然繊維と同程度の生分解速度を有しているため、積層不織布としても生分解性能に優れる不織布であることが認められた。
【０１３５】
実施例２４は、実施例２３よりも天然繊維不織ウエブの積層比率が多いため、得られた不織布はさらに吸水性に優れるとともに、複合長繊維が天然繊維と同程度の生分解速度を有しているため、生分解性能にも優れるものであった。また、長繊維不織ウエブが少ないために、不織布の強力についてはやや低いが、実用的な機械的特性を有するものであった。
【０１３６】
実施例２５は、実施例２３よりも天然繊維不織ウエブの積層比率が少ないため、吸水性についてはやや劣るが、実用的な機械的特性を有する積層不織布となり、しかも複合長繊維が天然繊維と同程度の生分解速度を有しているため、生分解性能にも優れるものであった。
【０１３７】
【表６】
【表７】
表６および表７から明らかなように、実施例２６〜２８においては、いずれも紡出糸条の冷却性および開繊性に問題もなく操業性は良好であり、しかも得られた不織布の性能は、実用的な強力を備え柔軟で生分解性に優れたものであった。
【０１４０】
実施例２９においては、高融点成分と低融点成分とにおける結晶核剤の添加量が同量であるため、紡出糸条の冷却性はやや低下するものの、操業性に特に問題はなかった。
【０１４１】
実施例３０においては、結晶核剤の全添加量が本発明の好ましい範囲よりも多すぎるため、紡出糸条の冷却性および開繊性には問題はなかったものの、得られた不織布の強力は実施例２６よりも若干劣るものであった。
【０１４２】
実施例３１においては、低融点成分としてさらに融点の低い重合体を用いたため、結晶核剤の効果が大きく寄与するものの、紡出糸条の冷却性および開繊性にはやや劣る結果であった。
【０１４４】
実施例３２においては、両成分ともに融点の低い重合体を用いたが、結晶核剤の効果が大きく寄与するため、紡出糸条の冷却性および開繊性に問題がないことが判った。
【０１４５】
【表８】
これに対して、表８から明らかなように、比較例１は、実施例１と同一の高融点成分を用いたものの、繊維横断面が本発明の範囲外である単相型であるので、紡出糸条の冷却性、可紡性、および開繊性も良好であり、機械的性能にも優れるものの、得られた不織布は生分解性能に乏しいものであった。
【０１４７】
比較例２は、実施例１と同一の低融点成分を用いたものの、繊維横断面が本発明の範囲外である単相型であるので、紡出糸条の冷却性、可紡性、および開繊性が不良であり目標とした不織布が得られなかった。
【０１４８】
比較例３は、紡出糸条の牽引速度が低く本発明の範囲外であるので、紡出糸条の冷却性、可紡性および開繊性に劣り、かつ、得られた不織布は機械的性能および寸法安定性に劣るものであった。
【０１４９】
比較例４は、天然繊維不織ウエブと長繊維不織ウエブとの積層不織布であるが、両ウエブの一体化を熱エンボスロールからなる熱圧接装置にて行ったので、天然繊維不織ウエブがローラーに取られ熱圧接固定ができず、天然繊維不織ウエブと長繊維不織ウエブとの一体化された積層不織布を得ることができなかった。
【０１５０】
【発明の効果】
本発明によれば、紡出糸条の冷却性および開繊性に優れ、かつ生分解性能が制御可能であるとともに不織布の機械的特性、地合いに優れ、さらに熱接着機能を有する生分解性不織布およびその製造方法を提供することができる。
【０１５１】
本発明の不織布は、おむつや生理用品その他の医療・衛生材料素材、使い捨ておしぼりやワイピングクロスなどの拭き取り布、使い捨て包装材、家庭・業務用の生ごみ捕集用袋その他廃棄物処理材などの生活関連用素材、あるいは、農業・園芸・土木用に代表される産業用資材の各素材として好適である。しかもこの不織布は、生分解性を有するので、その使用後に完全に分解消失するため、自然環境保護の観点からも有益であり、あるいは、例えば堆肥化して肥料とするなど再利用を図ることもできるため資源の再利用の観点からも有益である。
【図面の簡単な説明】
【図１】本発明の多葉型複合長繊維の繊維横断面のモデル図である。
【図２】本発明の多葉型複合長繊維の繊維横断面のモデル図である。
【図３】本発明の多葉型複合長繊維の繊維横断面のモデル図である。
【符号の説明】
１ 高融点成分
２ 低融点成分
３ 中心[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a biodegradable nonwoven fabric used for a wide range of applications such as medical and sanitary materials, living materials, and general industrial materials, and a method for producing the same.
[0002]
[Prior art]
As the biodegradable nonwoven fabric, for example, a biodegradable nonwoven fabric derived from natural fibers such as cotton, hemp, wool, rayon, chitin, and alginic acid is known. However, these biodegradable nonwoven fabrics are generally hydrophilic and have excellent water absorption, but on the other hand, these nonwoven fabrics have a remarkable decrease in strength and dimensional stability under a wet environment, and There was a limit to the development of some applications. Furthermore, since these nonwoven fabrics are non-thermoplastic, they have no thermoformability and are inferior in workability.
[0003]
As a biodegradable nonwoven fabric which solves these problems, JP-A-5-93318 or JP-A-5-195407 discloses a nonwoven fabric using a biodegradable thermoplastic polymer. However, in these, the spun bond method is inferior in the cooling property and spinnability of the spun yarn, so that it is difficult to produce by the spun bond method. Was something. This is because the melting point and the crystallization temperature of the biodegradable polymer are generally low, and the crystallization rate is low. In other words, in the cooling, traction thinning, collection, and deposition processes after melt spinning, the fibers cannot be sufficiently opened due to adhesion between the yarns, which impairs the formation of the obtained nonwoven fabric. In addition, it is difficult to control the biodegradation rate.
[0004]
In addition, conventional long fibers having a fiber cross section of a single type, a single hollow type, or the like composed of only one component have a relatively high melting point and relatively high crystallization temperature when producing a nonwoven fabric by a spun bond method. When the cooling property and the opening property of the spun yarn are emphasized using the degradable polymer, the biodegradability of the obtained nonwoven fabric is inferior. Conversely, if a biodegradable polymer having a relatively low melting point and a low crystallization temperature is used with an emphasis on biodegradability, the cooling and opening properties of the spun yarn are inferior. Moreover, in the conventional method, the biodegradation performance can be controlled to some extent by changing the type and fineness of the polymer to be applied, the composite ratio, the degree of fiber orientation, and the like, but delicate control is not possible. It was possible.
[0005]
Further, a nonwoven fabric formed of a long fiber alone using the biodegradable thermoplastic polymer as described above has excellent mechanical properties, but is inferior in hygroscopicity and water absorbency, and has a limited use. Was. As a method of improving this, it is conceivable to laminate natural fibers and the like having excellent water absorption.However, it is possible to laminate a nonwoven web composed of a long fiber made of a biodegradable thermoplastic polymer and a nonwoven web composed of natural fibers. In the case of performing partial heat fusion by using a conventional heat-pressing apparatus using an embossing roll, the adhesive strength between the two webs is weak, and the obtained laminated nonwoven fabric is not completely usable.
[0006]
[Problems to be solved by the invention]
The present invention solves such a problem, and the biodegradability is controllable, and the nonwoven fabric is excellent in texture and mechanical properties, spun yarn cooling and spinnability, and has a heat bonding function. An object of the present invention is to provide a biodegradable nonwoven fabric having the above-mentioned properties and, if necessary, exhibiting water absorbency, and a method for producing the same.
[0007]
[Means for Solving the Problems]
In order to solve this problem, the present invention has the following configuration as a gist.
(1) A nonwoven fabric in which a long-fiber non-woven web made of a composite long fiber is partially hot-pressed and maintained in a predetermined shape, wherein the composite long fiber is biodegradable first aliphatic polyester And a low-melting-point component comprising a second aliphatic polyester having a biodegradability having a lower melting point than the high-melting-point component.With traction speed of 2000m / min or moreThe multi-lobed conjugated long fiber, in the cross section of the fiber of the multi-lobed conjugated long fiber, the low-melting component forms a core, and the high-melting component forms circumferentially independent projections of the low-melting component. A plurality is formed, and the low-melting component is continuous without being divided by the high-melting component, and the high-melting component and the low-melting component forming the multi-leaf conjugate filament are both continuous in the fiber axis direction. A biodegradable nonwoven fabric characterized by being alternately exposed on a fiber surface.
[0008]
(2) A long fiber nonwoven web composed of a composite long fiber and a natural fiber nonwoven web composed of a natural fiber are laminated and integrated by partial pressure welding, and the first fat having a biodegradable composite long fiber A high melting point component comprising an aliphatic polyester and a low melting point component comprising a second aliphatic polyester having a lower melting point than the high melting point component and having biodegradability.With traction speed of 2000m / min or moreThe multi-lobed conjugated long fiber, in the cross section of the fiber of the multi-lobed conjugated long fiber, the low-melting component forms a core, and the high-melting component forms circumferentially independent projections of the low-melting component. A plurality is formed, and the low-melting component is continuous without being divided by the high-melting component, and the high-melting component and the low-melting component forming the multi-leaf conjugate filament are both continuous in the fiber axis direction. A biodegradable nonwoven fabric characterized by being alternately exposed on a fiber surface.
[0009]
(3) A method for producing a nonwoven fabric in which a long-fiber non-woven web made of a composite long fiber is partially hot-pressed to maintain a predetermined form, wherein the composite long fiber is biodegradable. It is formed using a high melting point component composed of an aliphatic polyester and a low melting point component composed of a second aliphatic polyester having a lower biodegradability and a lower melting point than the high melting point component. The high melting point component forms a plurality of circumferentially independent projections of the low melting point component in the fiber cross section, and the low melting point component is not divided by the high melting point component in the fiber cross section. The multi-leaf conjugated filaments are continuous and are melt-spun such that both the high melting point component and the low melting point component are continuous in the fiber axis direction and are alternately exposed on the fiber surface. After pulling thinned at a rate 2000 m / min or more, the long fiber nonwoven web and without producing method of the biodegradable nonwoven fabric, which comprises causing the long fiber nonwoven web is partially thermocompression bonding by thermal compression device.
[0010]
(4) A long-fiber non-woven web made of a composite long fiber and a natural-fiber non-woven web made of a natural fiber are laminated and partially press-fitted to be integrated to form a first fiber having biodegradability. Formed using a high melting point component composed of an aliphatic polyester and a low melting point component composed of a second aliphatic polyester having a lower biodegradability and a lower melting point than the high melting point component. The core is formed, and the high melting point component forms a plurality of circumferentially independent projections of the low melting point component in the fiber cross section, and the low melting point component is separated by the high melting point component in the fiber cross section. Melt-spun multifilament conjugated filaments that are continuous and that both the high-melting point component and the low-melting point component are continuous in the fiber axis direction and are alternately exposed on the fiber surface. After the fiber is drawn down at a drawing speed of 2000 m / min or more, it is converted into a long-fiber non-woven web. After the long-fiber non-woven web is laminated with a non-woven web of a natural fiber separately prepared by an ordinary method, an ultrasonic wave is applied. A method for producing a biodegradable nonwoven fabric, wherein both nonwoven webs are partially fused and integrated by performing a fusion treatment.
[0011]
According to the present invention, in the cross section of the long fiber, the high melting point component, which is inferior in biodegradability but excellent in cooling property and spreadability, is finely divided and positioned on the outer periphery of the fiber, thereby providing cooling property and spreadability. By positioning a low-melting component, which is inferior to biodegradability but excellent in biodegradability, at the center, a nonwoven fabric excellent in all of cooling properties, fiber opening properties and biodegradability can be obtained.
[0012]
In addition, among the biodegradable nonwoven fabrics of the present invention, a laminated nonwoven fabric obtained by laminating a long-fiber nonwoven web and a natural-fiber nonwoven web exhibits water absorption by natural fibers and has poor mechanical strength when wet. The properties of natural fibers are reinforced by a long-fiber non-woven web. Moreover, since the long-fiber non-woven web is composed of an aliphatic polyester-based polymer and the natural-fiber non-woven web is composed of a degradable material such as cotton, the constituent materials of the laminated nonwoven fabric of the present invention are all in a natural environment. It can be decomposed.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
First, among the biodegradable nonwoven fabrics of the present invention, a long-fiber nonwoven fabric in which a long-fiber nonwoven web is partially heated and pressed to maintain a predetermined form will be described.
[0014]
The long fiber applied to the present invention is formed of two components of aliphatic polyester having biodegradability. That is, the long fibers applied to the present invention are conjugate long fibers composed of an aliphatic polyester having a high melting point component and an aliphatic polyester having a low melting point component. In general, the high melting point component is excellent in the cooling property and the spreadability of the spun yarn, but is inferior in biodegradability due to high crystallinity, and conversely, the low melting point component is in cooling the spun yarn. Although it is inferior in openability and openability, it has excellent biodegradability due to low crystallinity. For example, when the fiber cross section is a single phase of a high-melting-point component, it is not possible to obtain the target biodegradation performance, although it is excellent in the spinning property and the nonwoven fabric. On the other hand, when the cross section of the fiber is a single phase of a low melting point component, the spun yarn is inferior in the cooling property, and even a nonwoven fabric cannot be obtained. According to the present invention, in the fiber cross-section of the long fiber, the high melting point component which is inferior in biodegradability but excellent in cooling property and spreadability is subdivided and located on the outer periphery of the fiber. By positioning a low-melting component, which is inferior but has excellent biodegradability, at the center, a nonwoven fabric excellent in all of cooling properties, fiber opening properties and biodegradability can be obtained.
[0015]
Therefore, in the long fiber according to the present invention, the difference in melting point between the high melting point component and the low melting point component is preferably 5 ° C or more, and more preferably 10 ° C or more. If the difference in melting point between the high melting point component and the low melting point component is less than 5 ° C, the fiber cross section approaches a full fusion type as in the case of a single phase. However, even high melting point components cause thermal damage, and the resulting nonwoven fabric cannot have mechanical properties and flexibility.
[0016]
Examples of the aliphatic polyester forming the multilobal conjugate long fiber in the present invention include poly (α-hydroxy acid) such as polyglycolic acid and polylactic acid, or poly (ε-caprolactone) and poly (β- Poly (.omega.-hydroxyalkanoate) such as propiolactone) or a copolymer comprising repeating unit elements constituting these, further comprises poly-3-hydroxypropionate, poly-3-hydroxybutyrate, poly-. Poly (β-hydroxyalkanoates) such as 3-hydroxycaproate, poly-3-hydroxyheptanoate, and poly-3-hydroxyoctanoate, and the repeating unit elements and poly-3-hydroxyvarianoate constituting them And copolymers with repeating unit elements constituting poly-4-hydroxybutyrate. Can be Further, as the one comprising a condensation polymer of diol and dicarboxylic acid, for example, polyethylene oxalate, polyethylene succinate, polyethylene adipate, polyethylene acetate, polybutylene oxalate, polybutylene succinate, polybutylene adipate, polybutylene sebacate , Polyhexamethylene sebacate, polyneopentyl oxalate, or a copolymer composed of repeating unit elements constituting these. Among the above aliphatic polyesters, polylactic acid or a copolymer of polyethylene succinate or polybutylene succinate or polybutylene adipate or polybutylene sebacate or a recurring unit element constituting the same has improved thread-forming properties and biodegradability. It is preferably used for reasons such as excellence.
[0017]
Further, among the aliphatic polyesters, a copolymerized polyester having butylene succinate as a main repeating unit is particularly suitable. At this time, the copolymerization ratio of butylene succinate is 80 mol% as a high melting point component. As described above, the low melting point component is preferably 70 to 90 mol%. If the copolymerization ratio of butylene succinate is too low, the biodegradability is excellent, but the spun yarn is inferior in cooling property and openability, and the desired long fiber and thus nonwoven fabric cannot be obtained. Conversely, if the copolymerization ratio of butylene succinate is too high, the cooling property and the spreadability are excellent, but the biodegradability is inferior and is not the object of the present invention.
[0018]
The melt flow rate value (hereinafter referred to as MFR value) of the polymer applied in the present invention is preferably such that the MFR value of the high melting point component and the low melting point component is 1 to 100 g / 10 min. It is preferable that the melting point component is 15 to 50 g / 10 minutes and the low melting point component is 20 to 70 g / 10 minutes. However, the MFR value in the present invention is measured according to the method described in ASTM-D-1238 (E). When the MFR value of the high melting point component is less than 15 g / 10 minutes and / or the MFR value of the low melting point component is less than 20 g / 10 minutes, the spun yarn is not smoothly smoothed because the viscosity is too high. As a result, the operability is impaired, and the resulting fibers have a large fineness and poor uniformity. Conversely, if the MFR value of the high melting point component exceeds 50 g / 10 min and / or the MFR value of the low melting point component exceeds 70 g / 10 min, not only the viscosity becomes too low, but also the composite cross section becomes unstable, In the spinning process, yarn breakage occurs, impairing operability, and resulting in poor mechanical properties of the obtained nonwoven fabric. For these reasons, the MFR value of the high melting point component is more preferably 12 to 45 g / 10 minutes, and the MFR value of the low melting point component is more preferably 18 to 65 g / 10 minutes.
[0019]
The viscosity of the high melting point component is preferably higher than the viscosity of the low melting point component. In general, in a cross section of a fiber obtained in the composite spinning of a thermoplastic polymer, a low-viscosity component acts to cover a high-viscosity component. That is, in the present invention, by making the high melting point component high in viscosity, the high melting point component in the circumferential direction can be easily made independent, and it is also suitable for increasing the degree of irregularity.
[0020]
In the present invention, the aliphatic polyester used for the high melting point component and the low melting point component has a number average molecular weight of about 20,000 or more, preferably 40,000 or more, and more preferably 60,000 or more, and has a high spinnability. It is good in terms of the properties of the obtained yarn. Further, in order to increase the degree of polymerization, a chain extended with a small amount of diisocyanate or tetracarboxylic dianhydride may be used.
[0021]
In the long fiber applied in the present invention, it is preferable that a crystal nucleating agent is added to at least the low melting point component of the constituent components. Addition of a nucleating agent can prevent adhesion between spun yarns even if the polymer has low crystallinity that is hard to solidify after melt spinning. The nucleating agent is added in the polymerization step or the melting step. In this case, it is preferable that the nucleating agent be dispersed as uniformly as possible in order to improve the mechanical performance and uniformity of the obtained yarn.
[0022]
The crystal nucleating agent is not particularly limited as long as it is a powdered inorganic substance and does not dissolve in a melt, but talc, calcium carbonate, titanium oxide, boron nitride, silica gel, magnesium oxide, and the like are usually used. Among them, talc, titanium oxide or a mixture thereof is particularly preferably used.
[0023]
The average particle size of the inorganic powder as the nucleating agent is preferably 5 μm or less. If the average particle size exceeds 5 μm, fibers having a finer size tend to be difficult to obtain, or a filter in a spinneret having a plurality of discharge holes is liable to be clogged. Tendency to decrease. For these reasons, the average particle size of the inorganic powder as a crystal nucleating agent is 5 μm or less, preferably 4 μm or less, and more preferably 3 μm or less.
[0024]
The bulk specific volume of the inorganic powder as a crystal nucleating agent is preferably 2 to 10 cc / g, and more preferably 3 to 8 cc / g. The bulk specific volume is the volume of the inorganic powder per unit weight. As the bulk specific volume increases, the surface area of the inorganic powder increases, and the effect as a crystal nucleating agent increases. When the bulk specific volume of the inorganic powder is less than 2 cc / g, the effect as a nucleating agent is reduced, and therefore, the amount of the nucleating agent added (content in the polymer) must be increased, The mechanical strength of the obtained long fiber and thus the nonwoven fabric is reduced. In addition, it is difficult to produce an inorganic powder having a bulk specific volume exceeding 10 cc / g. If such an inorganic powder is to be obtained, the cost of the inorganic powder rises, and the cost of the obtained long fiber also rises. It becomes.
[0025]
When the amount of the nucleating agent in the high melting point component is QA (% by weight) and the amount of the nucleating agent in the low melting point component is QB (% by weight), It is preferably added so as to satisfy the formulas (1) and (2).
[(ΔTA + ΔTB) / 100] −2 / 3 ≦ QA + QB ≦ [(ΔTA + ΔTB) / 100] +4 (1)
QA ≦ QB (2)
Where ΔTA = melting point of high melting point component−crystallization temperature of high melting point component ≧ 35
ΔTB = melting point of low melting point component−crystallization temperature of low melting point component ≧ 35
When the total addition amount of the crystal nucleating agent QA + QB (% by weight) exceeds the upper limit defined by the formula (1), the spun yarn has a high cooling effect, but the spinnability is reduced and the obtained long fiber and The mechanical performance of the nonwoven fabric is inferior and is not preferred. Conversely, if the total amount of the crystal nucleating agent QA + QB (% by weight) is lower than the lower limit defined by the formula (1), the cooling property of the spun yarn decreases, and adhesion occurs between the spun yarns. Then, it becomes difficult to obtain the target nonwoven fabric. Further, when the addition amount QA (% by weight) of the nucleating agent in the high melting point component is larger than the addition amount QB (% by weight) of the nucleating agent in the low melting point component, the cooling property of the high melting point component is reduced. Although the temperature is further improved, the cooling property of the low melting point component is lowered, which is not preferable because adhesion between spun yarns is likely to occur.
[0026]
By the way, in the equation (1), ΔT is a difference between the melting point and the crystallization temperature of each component. In the spinning process, the smaller the ΔT, the better the cooling property of the spun yarn. In the polymer of the present invention, ΔT is usually as large as 35 or more, but the cooling of the spun yarn can be effectively promoted by adding a nucleating agent.
[0027]
In the present invention, various additives such as a matting agent, a pigment, a light stabilizer, a weathering agent, an antioxidant, etc. may be added to the high melting point component or the low melting point component, or to both components, if necessary. Can be added in a range that does not impair the effect of the above.
[0028]
Next, the cross-sectional shape of the composite long fiber applied to the present invention will be described.
In the multi-leaf composite cross section of the present invention, the low melting point component forms a core, the high melting point component forms a plurality of circumferentially independent projections of the low melting point component, and the low melting point component is high. It is necessary for the high melting point component and the low melting point component to be continuous without being divided by the melting point component, to be continuous in the fiber axis direction, and to be alternately exposed on the fiber surface. More specifically, the high melting point component forms a plurality of individually independent protrusions in the circumferential direction of the low melting point component forming the core, that is, the low melting point component is continuous without being separated by the high melting point component. This is necessary to maintain good biodegradation performance. Further, it is necessary that both the high melting point component and the low melting point component be continuous in the fiber axis direction in order to improve the stability of the fiber cross section, the spinning property, and the mechanical properties of the fiber. Further, the fact that the high-melting point component and the low-melting point component are alternately exposed on the fiber surface is necessary for improving the cooling property and opening property of the spun yarn, and promoting and controlling the biodegradability.
[0029]
By applying a long fiber having such a fiber cross-sectional shape, for example, even if the low melting point component is a polymer inferior in cooling performance and openability, the high melting point component provided in the projections may cause the yarn to have a lower inter-filament length. Of the spun yarn can be prevented, and the cooling property and the spreadability of the spun yarn can be improved. Further, even if the high melting point component is a polymer having poor biodegradability, the biodegradability of the low melting point component provided in the core is excellent, so that the high melting point component is left as a small piece with time, Since the fineness of the small pieces is extremely small, the biodegradability as a nonwoven fabric is excellent.
[0030]
In the fiber cross section of the composite long fiber applied to the present invention, the number of projections of the high melting point component is preferably 4 to 10. If the number of protrusions of the high melting point component is less than 4, the cooling property, the opening property and the biodegradability of the spun yarn are inferior. That is, in the present invention, the higher the proportion of the high melting point component in the circumferential direction, the better the cooling and opening properties of the spun yarn. However, if the number of projections is less than 4, the lower the melting point, the lower the melting point. The circumferential occupancy of the components increases, resulting in poor cooling and opening properties. If the composite ratio of the high melting point component is increased to avoid this, the segment fineness of the individually high melting point component, that is, the fineness of the smallest constituent unit occupied by the high melting point component in the fiber cross section increases, Inevitably, the biodegradability of the nonwoven fabric is inferior. On the other hand, if the number of protrusions of the high melting point component exceeds 10, it is difficult to make each segment of the high melting point component individually independent, which is not preferable. For these reasons, the number of protrusions of the high melting point component is more preferably 5 to 10.
[0031]
Further, the peripheral ratio of the high melting point component / low melting point component in the fiber cross section of the composite long fiber applied to the present invention, that is, the ratio of the total perimeter occupied by each component in the outer periphery of the fiber cross section is the high melting point component / The low melting point component is preferably 90/10 to 40/60. For example, when the circumferential occupancy of the high melting point component in the outer periphery of the fiber cross section increases, the projection increases accordingly, and the circumferential occupancy of the low melting point component when the web is heat-welded is too small to be pressed easily. Only a nonwoven fabric having poor mechanical performance can be obtained. In addition, since the segment fineness of the high melting point component that is independent of each other also increases, the biodegradability of the nonwoven fabric tends to decrease. Conversely, when the circumferential occupancy of the low melting point component in the outer periphery of the fiber cross section increases, the spun yarn becomes less likely to be cooled, and fusion is likely to occur in the drawing / spreading step.
[0032]
In the fiber cross section of the composite long fiber applied to the present invention, the arrangement form of the segments of the high melting point component independently of each other is not limited as long as the fiber cross section shape is satisfied. It is preferred that the segments of the component are each equally spaced on the outer circumference of the fiber cross section. When each segment of the high melting point component is located on the outer periphery of the fiber cross section with a bias, the spun yarn generates kneeling in the spinning process, and the fibers are entangled when the web is hot pressed. It is difficult to uniformly provide the bonding point between the high melting point component and the low melting point component, and the nonwoven fabric tends to have strong unevenness. Further, it is preferable that all segments of the high melting point component are disposed so as to be buried in the low melting point component at the same ratio. When the segments of the high melting point component are buried in the low melting point component at different ratios, the fibers are less likely to be entangled when the web is hot pressed, and the high melting point component and the low melting point component are bonded. Since the points cannot be uniformly applied, the nonwoven fabric tends to have strong unevenness. In addition, as to what ratio each segment of the high melting point component is disposed so as to be buried in the low melting point component, for example, as shown in FIG. As shown in FIG. 2, the arrangement of the high
[0033]
The composite ratio of the high melting point component / low melting point component of the composite long fiber applied to the present invention is preferably 1/3 to 3/1 (weight ratio). If the compounding ratio is out of this range, it is not possible to satisfy all of the cooling property, the spreadability and the biodegradability of the spun yarn, and furthermore, it is preferable to induce instability of the fiber cross-sectional shape. Absent. For example, when the composite ratio of the high-melting-point component / low-melting-point component is more than 1/3, the biodegradability is excellent, but the cooling property and the opening property of the spun yarn are poor. Conversely, if the composite ratio of the high-melting-point component / low-melting-point component exceeds 3/1, the spun yarn has excellent cooling properties and openability, but poor biodegradability. For example, if the high melting point component is a polymer having poor biodegradability, the biodegradation rate can be accelerated by increasing the composite ratio of the low melting point component. For this reason, the composite ratio of the high melting point component / low melting point component is more preferably 1/2 to 2/1 (weight ratio).
[0034]
The fineness of each segment of the high melting point component of the composite filament applied to the present invention is preferably 0.05 to 2 denier. Here, the segment fineness of the high melting point component is the fineness of the minimum constituent unit occupied by the high melting point component in the fiber cross section. If each segment fineness of the high melting point component is less than 0.05 denier, it is not preferable because of a decrease in production amount and instability of the fiber cross-sectional shape. On the other hand, if the segment fineness of the high melting point component is more than 2 denier, the spun yarn is inferior in cooling performance and spreadability, and also inferior in biodegradability. For these reasons, the fineness of each segment of the high melting point component is more preferably 0.1 to 1 denier.
[0035]
Further, similarly to each segment fineness of the high melting point component, the single filament fineness of the composite long fiber applied to the present invention is preferably 1.5 to 10 denier. If the single yarn fineness is less than 1.5 denier, it is not preferable because the spinneret becomes complicated, the yarn breakage in the spinning process increases, the production amount decreases, and the fiber cross-sectional shape becomes unstable. Conversely, if it exceeds 10 denier, the cooling property of the spun yarn is inferior and the biodegradability is also inferior. For these reasons, the single-fiber fineness is more preferably 2 to 8 denier.
[0036]
Next, among the biodegradable nonwoven fabrics of the present invention, a laminated nonwoven fabric obtained by laminating a natural fiber nonwoven web on the long fiber nonwoven web and integrating them by ultrasonic fusion will be described.
[0037]
The natural fiber applied to the present invention is not particularly limited as long as it has biodegradability. In particular, cotton, ramie, silk fiber cut into short fibers, and the like are suitably used. Here, examples of the cotton include combed yarn that has not been subjected to bleaching processing, bleached cotton that has been subjected to bleaching processing, and bristles obtained from a woven or knitted fabric.
[0038]
The natural fiber nonwoven web in the present invention is a web made by combining the natural fibers singly or in combination, a parallel web arranged in the traveling direction of the card machine, a cross-laid web of the parallel web, a random arrangement. Either a random web or a semi-random web arranged at a medium level may be used, and it can be appropriately selected according to the intended use. In particular, when used for clothing, it is preferable to use a card web whose longitudinal / lateral strength ratio is approximately 1/1 in terms of strength as a nonwoven fabric.
[0039]
When laminating a natural fiber nonwoven web, the laminating ratio of the natural fiber nonwoven web and the long fiber nonwoven web is preferably 10/90 to 90/10 (% by weight). If the natural fiber content is less than 10% by weight, the mechanical properties of the laminated nonwoven fabric are excellent, but the hygroscopicity and water absorption cannot be sufficiently improved, and the purpose of laminating the natural fibers cannot be achieved. Not preferred. Conversely, when the content of the natural fiber exceeds 90% by weight, the mechanical properties are impaired although the hygroscopicity and the water absorbing property are excellent, which is not preferable. For these reasons, the lamination ratio of the natural fiber nonwoven web and the long fiber nonwoven web is more preferably 20/80 to 80/20 (% by weight).
[0040]
The integration of the laminated long fiber nonwoven web and the natural fiber nonwoven web is performed by an ultrasonic fusion treatment. This ultrasonic fusion treatment is to form a partial fusion zone using an ultrasonic fusion device to be described later, and heat the composite long fiber in the fusion zone and bury it inside the natural fiber. Thereby, the long fiber nonwoven web and the natural fiber nonwoven web are fused. This makes it possible to integrate the long-fiber nonwoven web and the natural fiber having no thermal adhesiveness with an adhesive force that can withstand practical use.
[0041]
As described above, the biodegradable nonwoven fabric of the present invention is a nonwoven fabric composed of multilobal conjugated long fibers composed of a high melting point component and a low melting point component having different biodegradability, and a composite ratio of both components. By combining the number of protrusions of the high melting point component, the fineness of each segment of the high melting point component, the fineness of a single yarn, etc., it is possible to control the required cooling property, spreadability and biodegradability of the spun yarn. .
[0042]
Next, a method for producing the biodegradable nonwoven fabric of the present invention will be described.
First, among the biodegradable nonwoven fabrics of the present invention, a method for producing a long-fiber nonwoven fabric in which a long-fiber nonwoven web is partially heated and held in a predetermined form will be described.
[0043]
The production of the biodegradable nonwoven fabric of the present invention can be carried out using an ordinary composite spinning apparatus. First, a biodegradable aliphatic polyester having an MFR value of the high melting point component of 15 to 50 g / 10 minutes and an MFR value of the low melting point component of 20 to 70 g / 10 minutes as described above, that is, Butylene succinate or a copolymerized polyester containing butylene succinate having a copolymerization ratio of butylene succinate of 80 mol% or more as a main repeating unit, and a copolymerization ratio of butylene succinate as a low melting point component being 70 to 90 mol. % Butylene succinate as the main repeating unit is used as a suitable material, and these are melted separately, and the composite ratio of the high melting point component / low melting point component is 1/3 to 3/1 (weight ratio). After individually weighing so as to obtain a fiber that satisfies the above-mentioned number of protrusions of the high melting point component, each segment fineness of the high melting point component, and single yarn fineness. The spun yarns were discharged from multileaf type composite spinneret capable of forming a cross-sectional structure is cooled by a known cooling device using a cooling air flow. Next, it is pulled down using a take-off means such as air soccer so as to have a target fineness, and is taken out. After the drawn filaments are spread with a known spreading device, the fibers are spread and deposited on a movable collecting surface such as a screen conveyor to form a long nonwoven web. Thereafter, the long fiber nonwoven web is partially hot-pressed by using a hot-pressing apparatus to obtain a biodegradable nonwoven fabric.
[0044]
In the method for producing a biodegradable nonwoven fabric of the present invention, by adding the above-mentioned nucleating agent to the polymer used, particularly the polymer constituting the low melting point component, the adhesion of the spun yarn is prevented, and the cooling property is improved. , Opening property can be improved.
[0045]
In the melt spinning, the spinning temperature varies depending on the aliphatic polyester used, but can be appropriately set in consideration of at least the MFR value of the polymer and the fiber forming property, that is, the spinning property. Usually, the spinning temperature is a temperature at least 40 ° C. higher than the melting point of the polymer, and particularly preferably 120 to 300 ° C. If the spinning temperature is lower than 120 ° C., an unmelted polymer is generated or the melt viscosity is too high, so that it is difficult to extrude the polymer using a melt extruder. If the temperature exceeds ℃, the polymer starts to thermally decompose, and thus both are not preferred.
[0046]
The traction speed needs to be 2000 m / min or more, and especially 2500 m / min or more is more preferable because the dimensional stability of the nonwoven fabric is improved. If the drawing speed is less than 2000 m / min, the spun yarn is inferior in cooling property, spinnability and spreadability, and furthermore, the resulting nonwoven fabric is inferior in mechanical performance and dimensional stability.
[0047]
When performing a partial thermal pressure welding treatment on a long-fiber non-woven web, a method of forming a point fusion zone between long fibers using a heated embossing roll and a metal roll having a smooth surface, or ultrasonic wave A method is used in which a point-like fusion zone is formed between the long fibers of the pattern portion by applying a high frequency of ultrasonic waves on a pattern roll using a fusion device.
[0048]
The partial heat-welding means that the low-melting component and the high-melting component are hot-pressed between the constituent fibers to maintain the web form, and at least the high-melting components are not fused together and the constituent fibers It refers to thermal pressure welding that can prevent complete fusion, and by using such partial thermal pressure welding, biodegradability and flexibility can be exhibited while maintaining a predetermined nonwoven fabric form.
[0049]
The pressure-welded area formed by the partial heat-welding has a specific area with respect to the entire surface area of the long-fiber nonwoven web. Specifically, the individual heat-welded areas are round, elliptical, diamond-shaped. Any shape such as a mold, a triangle, a T-shape, and a well may be used.2 Having an area of 10 to 120 points / cm.2 , Preferably 20 to 60 points / cm2 It is good. Pressure contact density 10 points / cm2 If it is less than this, the mechanical properties and dimensional stability of the obtained nonwoven fabric are not improved, and conversely, the contact density is 120 points / cm.2 If it exceeds 3, the flexibility and the bulkiness are not improved, and both are not preferred. Further, the ratio of the area of the entire heat-welded region to the entire surface area of the web, that is, the contact area ratio is preferably 3 to 40%, and more preferably 4 to 30%. If the pressed area ratio is less than 3%, the obtained nonwoven fabric has poor dimensional stability, which is not preferable. Conversely, if the pressed area ratio exceeds 40%, the flexibility and bulkiness of the obtained nonwoven fabric will be impaired, and the biodegradability will also be poor.
[0050]
When a heated embossing roll is used, the surface temperature of the roll, that is, the processing temperature, must be lower than the melting point of the low melting point component. When the melting point of the low melting point component is exceeded, not only does the polymer adhere to the thermal pressure welding device, significantly impairing the operability, but also the texture of the nonwoven fabric becomes hard and a flexible nonwoven fabric cannot be obtained.
[0051]
In the case of using an ultrasonic fusion device, a device including an ultrasonic oscillator having a frequency of about 20 kHz, which is usually called a horn, and a pattern roll having a point-like or band-like convex protrusion on the circumference is employed. You. The pattern roll is disposed below the ultrasonic oscillator, and the long fiber nonwoven web can be partially heat-sealed by passing the web between the ultrasonic oscillator and the pattern roll. The pattern roll may have one row or a plurality of rows of convex protrusions. If the row has a plurality of rows, any of parallel or staggered arrangement may be used.
[0052]
Note that the partial heat-pressing treatment may be performed in either a continuous process or a separate process. In addition, for the heat-pressing treatment, any of the above-described heated embossing roll or ultrasonic fusing device may be selected. When an ultrasonic fusion device is used as a general life-related material such as a wipe cloth, a nonwoven fabric having excellent performance can be obtained.
[0053]
Next, among the biodegradable nonwoven fabrics of the present invention, a method for obtaining a laminated nonwoven fabric obtained by laminating a long fiber nonwoven web and a natural fiber nonwoven web will be described.
On the long-fiber non-woven web spread and deposited on the movable collection surface in the same manner as described above, a natural fiber separately prepared by an ordinary method is laminated, and subjected to ultrasonic fusion treatment to be integrated. Obtain a laminated nonwoven fabric.
[0054]
When performing the ultrasonic fusion treatment, the same ultrasonic fusion device as that in the case of the above-described partial thermal pressure welding treatment is preferably used. Specifically, air pressure is used for pressurizing the roll, and the linear pressure at which the horn contacts the roll is preferably in the range of 1.0 to 50 kg / cm. When the linear pressure is less than 1.0 kg / cm, the pressing pressure becomes insufficient with respect to the thickness of the laminated nonwoven fabric, and the peel strength of the laminate becomes small, which is not preferable. Conversely, if the linear pressure exceeds 50 kg / cm, the pressure is excessively applied to the fused portion, and the formation of a film at the fused portion similarly causes a decrease in adhesive strength, which is not preferable.
[0055]
In the present invention, before laminating the long fiber non-woven web and the natural fiber non-woven web spread and deposited on the movable collection surface, a preliminary heat-pressing treatment or a hot-air bonding treatment is applied to the long fiber non-woven web in advance. Alternatively, it is preferable to perform a three-dimensional confounding process by a known method. Thereby, when laminating the long fiber nonwoven web and the natural fiber nonwoven web, the form of the long fiber nonwoven web can be preliminarily maintained.
[0056]
The basis weight of the biodegradable nonwoven fabric of the present invention is not particularly limited because it is selected according to the purpose of use, but generally is 10 to 150 g / m2.2 Is more preferable, and more preferably 15 to 70 g / m.2 Range. The basis weight is 10 g / m2 If it is less than 10, the flexibility and the biodegradation rate are excellent, but the mechanical strength is inferior and it is not practical. Conversely, the basis weight is 150 g / m2 If it exceeds, the nonwoven fabric has a hard texture and is inferior in flexibility.
[0057]
【Example】
Next, the present invention will be specifically described based on examples, but the present invention is not limited to these examples.
[0058]
In the examples, the measurement of each physical property value was performed by the following method.
Melt flow rate value (g / 10 minutes): Measured at a temperature of 190 ° C. according to the method described in ASTM-D-1238 (E). (Hereafter referred to as MFR value)
[0059]
Melting point (° C.): Temperature at which the maximum value of the melting endotherm curve obtained by measuring the sample weight at 5 mg and the temperature rising rate at 20 ° C./min using a differential scanning calorimeter DSC-2 manufactured by Perkin Elmer Co., Ltd. Was taken as the melting point (° C.).
[0060]
Crystallization temperature (° C.): Using a differential scanning calorimeter DSC-2 manufactured by Perkin Elmer, the maximum value of the solidification exothermic curve obtained by measuring the sample weight at 5 mg and the heating rate at 20 ° C./min. The given temperature was taken as the crystallization temperature (° C.).
[0061]
Cooling property: The spun yarn was visually observed and evaluated on the following four levels.
A: No cohesive yarn is observed.
；: A small amount of cohesive yarn was observed.
Δ: There are cohesive yarns, and fibers are partially bundled.
×: Most of the fibers adhered and the fiber could not be opened.
[0062]
Opening property: The long-fiber nonwoven web formed by the spun yarn discharged from the opening device was visually evaluated on the following four scales.
A: The constituent fibers are separated, and no cohesive yarn and convergent yarn are observed.
；: Cohesive yarns and convergent yarns were slightly observed.
Δ: There are cohesive yarn and convergent yarn, and the spreadability is slightly poor.
×: Most of the constituent fibers adhered, and the spreadability was poor.
[0063]
-Weight (g / m2 ); From the sample in the standard state, 10 sample pieces each having a sample length of 10 cm and a sample width of 10 cm were prepared and adjusted to equilibrium moisture. Then, the weight (g) of each sample piece was weighed, and the average of the obtained values was calculated. Converted per unit area and weight per unit area (g / m2 ).
[0064]
-Strength of nonwoven fabric (kg / 5 cm width): Measured according to the method described in JIS-L-1096A. That is, ten sample pieces each having a sample length of 20 cm and a sample width of 5 cm were prepared, and a constant-speed extension-type tensile tester (Tensilon UTM-4-1- manufactured by Toyo Baldwin Co., Ltd.) was used for each sample piece in the longitudinal direction of the nonwoven fabric. Using 100), the film was stretched at a tensile speed of 10 cm / min, and the average value of the obtained load values at cutting was defined as the strength (kg / 5 cm width).
[0065]
-Compression stiffness (g) of the nonwoven fabric: 5 sample pieces each having a sample length of 10 cm and a sample width of 5 cm are prepared, and each sample piece is bent in the lateral direction to form a cylindrical body, and each end is joined. The sample thus obtained was used as a sample for measurement of compression bending resistance. Next, each measurement sample was compressed at a compression rate of 5 cm / min in the axial direction using a constant-speed extension type elongation tester (Tensilon UTM-4-1-100 manufactured by Toyo Baldwin Co., Ltd.). The average value of the maximum load values (g) was defined as the compression bending resistance (g). It should be noted that the compression softness means that the smaller the value, the better the flexibility.
[0066]
-Biodegradation performance: The nonwoven fabric is buried in the soil and taken out after 6 months. If the nonwoven fabric does not retain its form, or even if it retains its form, the strength is higher than the initial strength before embedding. When the biodegradability is reduced to 50% or less, the biodegradation performance is considered to be good (; O). When the strength is reduced to 75% or less of the initial strength before embedding, the biodegradation performance is normal ( △), and when the strength exceeds 75% of the strength initial value before embedding, the biodegradability was evaluated as poor (; ×).
[0067]
-Delamination strength (g / 5 cm width): A total of three sample pieces each having a sample length of 15 cm and a sample width of 5 cm were prepared, and a constant-speed extension-type tensile tester (Toyo Ball) was prepared for each sample in the longitudinal direction of the nonwoven fabric. Using Tensilon UTM-4--1-100 manufactured by Win Co., Ltd., the end of the long-fiber nonwoven web and the end of the natural-fiber nonwoven web in the laminated nonwoven fabric were gripped by the upper and lower chucks, and the peeling speed was 5 cm. The average value of the load values obtained by forcibly peeling off a length of 5 cm at a rate of / g / min was defined as delamination (g / 5 cm width).
[0068]
・ Water absorption (mm): Measured according to the birec method described in JIS-L-1096. That is, five sample pieces each having a sample length of 20 cm and a sample width of 2.5 cm were prepared, and each sample piece was pinned on a horizontal bar supporting a certain height on a water tank filled with water at 20 ± 2 ° C. And hang it. Align the lower end of the sample with the horizontal bar and lower the horizontal bar so that 1 cm of the lower end of the sample is just immersed in water. The height (mm) at which water had risen after standing for 10 minutes was measured, and the average value was taken as the water absorption (mm).
[0069]
Example 1
Polybutylene succinate having an MFR value of 20 g / 10 min and a melting point of 114 ° C. and a crystallization temperature of 75 ° C. is used as a high melting point component, and a low melting point component having an MFR value of 30 g / 10 min and a melting point of 102 ° C. and a crystallization temperature of 52 ° C. Using a copolymerized polyester of butylene succinate / ethylene succinate at 85 ° C. = 85/15 (mol%), a nonwoven fabric made of multi-leaf type composite long fibers was produced.
[0070]
That is, the two components are individually weighed so that the composite ratio of the high melting point component / the low melting point component becomes 1/1 (weight ratio), and then melted at a temperature of 180 ° C. using an individual extruder-type melt extruder. Then, using a spinneret having a fiber cross-section (the number of high-melting-point component protrusions = 6) having a high-melting-point component arrangement form as shown in FIG. It was melt spun. After cooling the spun yarn with a known cooling device, the yarn was drawn and thinned at a drawing speed of 4200 m / min using an air sucker installed below the die. Next, the fiber is spread with a known fiber opening device, and a single yarn fineness of 4.1 denier (high-melting-point component segment fineness = 0.34 denier × 6, low-melting-point component segment fineness = 2.0 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m.2 Was obtained. The area of 0.6mm2 Contact point density of 20 points / cm2 The processing temperature was 95 ° C. using a hot embossing roll provided with a pressing area ratio of 15% and a metal roll having a smooth surface. Table 1 shows the operability, non-woven fabric properties, and biodegradability.
[0071]
Example 2
Same as Example 1 except that a butylene succinate / butylene adipate = 80/20 (mol%) copolymer polyester having an MFR value of 30 g / 10 min, a melting point of 105 ° C. and a crystallization temperature of 29 ° C. is used as the low melting point component. Under the conditions, the multi-leaf type composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn with an air soccer at a drawing speed of 3900 m / min and drawn. Next, the yarn is spread with a known spreading device, and a single yarn fineness of 4.4 denier (high-melting-point component segment fineness = 0.37 denier × 6, low-melting-point component segment fineness = 2.2 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m.2 Was obtained. The conditions of the heat pressing were the same as in Example 1 except that the processing temperature was 98 ° C. Table 1 shows the operability, non-woven fabric properties, and biodegradability.
[0072]
Example 3
Example 1 except that a butylene succinate / butylene sebacate = 85/15 (mol%) copolymer polyester having an MFR value of 30 g / 10 min, a melting point of 105 ° C., and a crystallization temperature of 32 ° C. was used as the low melting point component. Under the same conditions, the multifilament type composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn using an air sucker at a drawing speed of 3800 m / min, and was drawn. Next, the fiber is opened by a known opening device, and a single yarn fineness of 4.5 denier (high-melting-point component segment fineness = 0.38 denier × 6, low-melting-point component segment fineness = 2.3 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m.2 Was obtained. The conditions of the heat pressing were the same as in Example 1 except that the processing temperature was 98 ° C. Table 1 shows the operability, non-woven fabric properties, and biodegradability.
[0073]
Example 4
As the high melting point component, a butylene succinate / ethylene succinate = 80/20 (mol%) copolymerized polyester having an MFR value of 20 g / 10 min, a melting point of 96 ° C., and a crystallization temperature of 40 ° C. is used. Under the same conditions as in Example 1 except that a copolymerized polyester of butylene succinate / ethylene succinate = 70/30 (mol%) having a melting point of 90 ° C. and a crystallization temperature of 25 ° C. at 30 g / 10 minutes was used. Multileaf type composite filaments were melt spun. After cooling the spun yarn with a known cooling device, the yarn was drawn with an air sucker at a drawing speed of 3700 m / min, and was drawn. Next, the yarn is spread with a known spreader, and a single yarn fineness of 4.6 denier (high-melting-point component segment fineness = 0.39 denier × 6, low-melting-point component segment fineness = 2.3 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m.2 Was obtained. The thermal welding conditions were the same as in Example 1 except that the processing temperature was 83 ° C. Table 1 shows the operability, non-woven fabric properties, and biodegradability.
[0074]
Example 5
Example 1 was repeated except that a butylene succinate / ethylene succinate = 95/5 (mol%) copolymer polyester having an MFR value of 30 g / 10 min, a melting point of 108 ° C, and a crystallization temperature of 68 ° C was used as the low melting point component. Under the same conditions, the multifilament type composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn with an air sucker at a drawing speed of 4200 m / min and drawn. Next, the fiber is spread with a known fiber opening device, and a single yarn fineness of 4.1 denier (high-melting-point component segment fineness = 0.34 denier × 6, low-melting-point component segment fineness = 2.0 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2Was obtained. The thermal welding conditions were the same as in Example 1 except that the processing temperature was 100 ° C. Table 1 shows the operability, non-woven fabric properties, and biodegradability.
[0075]
Example 6
Same as Example 1 except that a butylene succinate / butylene adipate = 90/10 (mol%) copolymerized polyester having an MFR value of 20 g / 10 min, a melting point of 110 ° C. and a crystallization temperature of 52 ° C. was used as a high melting point component. Under the conditions, the multi-leaf type composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn and thinned at a drawing speed of 3500 m / min by using an air sucker. Next, the yarn is spread with a known spreader, and a single yarn fineness of 4.9 denier (high melting point component fineness = 0.41 denier × 6, low melting point component fineness = 2.4 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m.2 Was obtained. The thermal pressing conditions were the same as in Example 1. Table 2 shows the operability, physical properties of the nonwoven fabric, and biodegradability.
[0076]
Example 7
Example 1 except that a butylene succinate / butylene sebacate = 90/10 (mol%) copolymerized polyester having an MFR value of 20 g / 10 min, a melting point of 110 ° C., and a crystallization temperature of 54 ° C. was used as a high melting point component. Under the same conditions, the multifilament type composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn with an air sucker at a drawing speed of 3400 m / min, and was drawn. Next, the fiber is opened by a known opening device, and a single yarn fineness of 5.0 denier (high-melting-point component segment fineness = 0.42 denier × 6, low-melting-point component segment fineness = 2.5 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m.2 Was obtained. The thermal pressing conditions were the same as in Example 1. Table 2 shows the operability, physical properties of the nonwoven fabric, and biodegradability.
[0077]
Example 8
Poly-L-lactic acid having an MFR value of 12 g / 10 min and a melting point of 178 ° C. and a crystallization temperature of 103 ° C. is used as a high melting point component, and a low melting point component having an MFR value of 35 g / 10 min and a melting point of 154 ° C. and a crystallization temperature of 28 ° C. Multi-lobed conjugated long fiber under the same conditions as in Example 1 except that a copolyester of L-lactic acid / ε-caprolactone at 85 ° C. = 85/15 (mol%) was used and the spinning temperature was 240 ° C. Was melt spun. After cooling the spun yarn with a known cooling device, the yarn was drawn using an air sucker at a drawing speed of 3800 m / min, and was drawn. Next, the fiber is opened by a known opening device, and a single yarn fineness of 4.5 denier (high-melting-point component segment fineness = 0.38 denier × 6, low-melting-point component segment fineness = 2.3 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m.2 Was obtained. The thermal pressure welding was performed under the same conditions as in Example 1 except that the processing temperature was 147 ° C. Table 2 shows the operability, physical properties of the nonwoven fabric, and biodegradability.
[0078]
Example 9
Example 1 except that a butylene succinate / ethylene succinate = 70/30 (mol%) copolymerized polyester having an MFR value of 30 g / 10 min, a melting point of 92 ° C, and a crystallization temperature of 20 ° C was used as the low melting point component. Under the same conditions, the multifilament type composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn with an air soccer at a drawing speed of 3900 m / min and drawn. Next, the yarn is spread with a known spreading device, and a single yarn fineness of 4.4 denier (high-melting-point component segment fineness = 0.37 denier × 6, low-melting-point component segment fineness = 2.2 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The conditions of the thermal pressure welding were the same as in Example 1 except that the processing temperature was 85 ° C. Table 2 shows the operability, physical properties of the nonwoven fabric, and biodegradability.
[0079]
Example 10
Example 1 except that a butylene succinate / ethylene succinate = 90/10 (mol%) copolymerized polyester having an MFR value of 30 g / 10 min, a melting point of 108 ° C. and a crystallization temperature of 57 ° C. was used as the low melting point component. Under the same conditions, the multifilament type composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn with an air sucker at a drawing speed of 4200 m / min and drawn. Next, the fiber is spread with a known fiber opening device, and a single yarn fineness of 4.1 denier (high-melting-point component segment fineness = 0.34 denier × 6, low-melting-point component segment fineness = 2.0 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The heat welding conditions were the same as in Example 1, except that the processing temperature was 101 ° C. Table 2 shows the operability, physical properties of the nonwoven fabric, and biodegradability.
[0080]
Example 11
Polybutylene succinate having an MFR value of 5 g / 10 min and a melting point of 114 ° C. and a crystallization temperature of 75 ° C. is used as a high melting point component, and a low melting point component having an MFR value of 10 g / 10 min and a melting point of 102 ° C. and a crystallization temperature. Under the same conditions as in Example 1 except that a copolymerized polyester of butylene succinate / ethylene succinate = 85/15 (mol%) at 52 ° C. was used, a multi-lobed conjugated filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn and thinned at a drawing speed of 3500 m / min by using an air sucker. Next, the yarn is spread with a known spreader and placed on a moving screen conveyor with a single yarn fineness of 4.9 denier (high melting point component fineness = 0.41 denier × 6, low melting component fineness = 2.5 denier). ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The thermal pressing conditions were the same as in Example 1. Table 2 shows the operability, physical properties of the nonwoven fabric, and biodegradability.
[0081]
Example 12
Polybutylene succinate having an MFR value of 50 g / 10 min, a melting point of 114 ° C. and a crystallization temperature of 75 ° C. is used as the high melting point component, and a low melting point component having an MFR value of 60 g / 10 min, a melting point of 102 ° C. and a crystallization temperature of 52 ° C. Under the same conditions as in Example 1 except that a copolymerized polyester of butylene succinate / ethylene succinate at 85 ° C. = 85/15 (mol%) was used, a multi-lobed conjugated continuous fiber was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn with an air sucker at a drawing speed of 4500 m / min, and was drawn. Next, the fiber is opened with a known opening device, and a single yarn fineness of 3.8 denier (high-melting-point component segment fineness = 0.32 denier × 6, low-melting-point component segment fineness = 1.9 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The thermal pressing conditions were the same as in Example 1. Table 2 shows the operability, physical properties of the nonwoven fabric, and biodegradability.
[0082]
Example 13
Same as Example 1 except that the same two components as in Example 1 were used as raw materials and a spinneret having a fiber cross-section (the number of high-melting-point component protrusions = 6) as shown in FIG. 1 was used. Under the conditions, the multi-leaf type composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn and thinned at a drawing speed of 3800 m / min using an air sucker, and was taken out. Next, the fiber is opened by a known opening device, and a single yarn fineness of 4.5 denier (high-melting-point component segment fineness = 0.38 denier × 6, low-melting-point component segment fineness = 2.3 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The thermal welding conditions were the same as in the example. Table 3 shows the operability, non-woven fabric properties, and biodegradability.
[0083]
Example 14
Example 2 Except that the same two components as in Example 1 were used as the raw materials, and the number of protrusions of the high melting point component was 4, and a spinneret having a fiber cross section having the same arrangement as in FIG. 3 was used. Under the same conditions as in Example 1, the multi-lobed composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn and thinned at a drawing speed of 4000 m / min using an air sucker, and was taken out. Next, the fiber is spread with a known fiber opening device, and a single-fiber fineness of 4.3 denier (high-melting-point component segment fineness = 0.53 denier × 4, low-melting-point component segment fineness = 2.1 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The thermal welding conditions were the same as in the example. Table 3 shows the operability, non-woven fabric properties, and biodegradability.
[0084]
Example 15
Example 2 Except for using the same two components as in Example 1 and using a spinneret having a number of protrusions of the high melting point component of 10 and a fiber cross-section having the same arrangement as in FIG. Under the same conditions as in Example 1, the multi-lobed composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn down using an air sucker at a drawing speed of 4300 m / min, and was taken out. Next, the fiber is opened with a known opening device, and a single yarn fineness of 4.0 denier (high-melting-point component segment fineness = 0.20 denier × 10, low-melting-point component segment fineness = 2.0 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The thermal welding conditions were the same as in the example. Table 3 shows the operability, non-woven fabric properties, and biodegradability.
[0085]
Example 16
The same two components as in Example 1 were used as raw materials, and individually weighed so that the composite ratio of the high-melting-point component / low-melting-point component became 1/3 (weight ratio). Under the same conditions as in Example 1, except for the following, the multifilament type composite continuous fiber was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn and thinned at a drawing speed of 4000 m / min using an air sucker, and was taken out. Next, the fiber is opened with a known opening device, and a single-fiber fineness of 4.5 denier (high-melting-point component segment fineness = 0.19 denier × 6, low-melting-point component segment fineness = 3.4 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The thermal welding conditions were the same as in the example. Table 3 shows the operability, non-woven fabric properties, and biodegradability.
[0086]
Example 17
The same two components as in Example 1 were used as raw materials, and individually weighed so that the composite ratio of the high-melting-point component / low-melting-point component was 3/1 (weight ratio), and the single-hole discharge rate was 2.0 g / min. Under the same conditions as in Example 1, except for the following, the multifilament type composite continuous fiber was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn with an air sucker at a drawing speed of 4400 m / min, and was drawn. Next, the yarn is spread with a known spreading device and placed on a moving screen conveyor, with a single yarn fineness of 4.1 denier (high melting point component fineness = 0.51 denier x 6, low melting component fineness = 1.0 denier). The fiber was spread and deposited as a long-fiber non-woven web composed of composite long fibers of This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The thermal pressing conditions were the same as in Example 1. Table 3 shows the operability, non-woven fabric properties, and biodegradability.
[0087]
Example 18
The same two components as in Example 1 were used as raw materials, and individually weighed so that the composite ratio of the high-melting-point component / low-melting-point component became 1/4 (weight ratio). Under the same conditions as in Example 1, except for the following, the multifilament type composite continuous fiber was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn with an air sucker at a drawing speed of 3300 m / min and drawn. Next, the fiber is opened by a known opening device and a single yarn fineness of 5.5 denier (high-melting-point component segment fineness = 0.18 denier × 6, low-melting-point component segment fineness = 4.4 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. The operability is shown in Table 3.
[0088]
Example 19
The same two components as in Example 1 were used as raw materials, and individually weighed so that the composite ratio of the high-melting-point component / low-melting-point component was 4/1 (weight ratio), and the single-hole discharge rate was 2.0 g / min. Under the same conditions as in Example 1, except for the following, the multifilament type composite continuous fiber was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn down at a drawing speed of 4400 m / min using an air sucker and pulled out. Next, the yarn is spread with a known spreading device, and a single yarn fineness of 4.1 denier (high-melting-point component segment fineness = 0.55 denier × 6, low-melting-point component segment fineness = 0.8 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The thermal pressing conditions were the same as in Example 1. Table 3 shows the operability, non-woven fabric properties, and biodegradability.
[0089]
Example 20
Under the same conditions as in Example 1, multi-leaf type composite long fibers were melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn using air soccer at a drawing speed of 2,000 m / min, and was drawn. Next, the fiber is spread with a known fiber opening device, and a single yarn fineness of 8.6 denier (high-melting-point component segment fineness = 0.71 denier × 6, low-melting-point component segment fineness = 4.3 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The thermal pressing conditions were the same as in Example 1. Table 4 shows the operability, physical properties of the nonwoven fabric, and biodegradability.
[0090]
Example 21
Under the same conditions as in Example 1, the multifilament type composite filament was melt-spun, then drawn and thinned, and opened to obtain a single yarn fineness of 4.1 denier (high-melting point component segment fineness = 0.34 denier × 6, low-melting-point component segment fineness = 2.0 deniers). The long-fiber nonwoven web was hot-pressed with an ultrasonic welding device, and the basis weight was 30 g / m.2 Was obtained. The condition of heat welding is that the area is 0.6mm2 Contact point density of 20 points / cm2The frequency was set to 19.5 kHz using a roll provided with a pressed area ratio of 15%. Table 4 shows the operability, physical properties of the nonwoven fabric, and biodegradability.
[0091]
Example 22
Under the same conditions as in Example 1, multifilament type composite filaments were melt-spun, then drawn and thinned, and opened to obtain a single yarn fineness of 4.1 denier (high melting point component segment fineness = 0.34 denier × 6). , Low melting point component segment fineness = 2.0 denier). This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The conditions of the thermal pressing were the same as in Example 1 except that the processing temperature was 98 ° C. Table 4 shows the operability, physical properties of the nonwoven fabric, and biodegradability.
[0092]
Example 23
A long-fiber nonwoven web composed of multi-leaf composite long fibers was obtained, and a laminated nonwoven fabric obtained by laminating a nonwoven web composed of natural fibers was obtained. That is, under the same conditions as in Example 1, the long-fiber nonwoven web spread and deposited on the movable collection surface was preliminarily heat-welded by a heat-welding device composed of an embossing roll. The area of 0.6mm2 Contact point density of 20 points / cm2 The processing temperature was 55 ° C. using a hot embossing roll provided with a pressed area ratio of 15% and a metal roll having a smooth surface. On the other hand, bleached cotton is used as the nonwoven web made of natural fibers, and the basis weight is 25 g / m2 by a random card machine.2 Created a card web.
[0093]
Then, the natural fiber non-woven web made of cotton is laminated by exposing to the above-mentioned long fiber non-woven web which has been subjected to the preliminary thermal pressure welding treatment, and subjected to a fusion treatment with an ultrasonic fusion device to obtain a basis weight of 50 g / m.2 Was obtained. The conditions for the fusion treatment were a frequency of 19.7 kHz and an area of 0.4 cm.2 The roll having the engraved pattern was provided with a convex portion, and the pressing was performed at a convex contact area ratio of 15% and a linear pressure of 2.0 kg / cm. Table 5 shows operability, physical properties of nonwoven fabric, and biodegradability.
[0094]
Example 24
Using the same long fiber nonwoven web and natural fiber nonwoven web as in Example 23, the basis weight of the long fiber nonwoven web was 10 g / m.2 And the basis weight of the natural fiber nonwoven web is 40 g / m2 Except that the basis weight was 50 g / m under the same conditions as in Example 23.2 Was obtained. Table 5 shows operability, physical properties of nonwoven fabric, and biodegradability.
[0095]
Example 25
Using the same long fiber nonwoven web and natural fiber nonwoven web as in Example 23, the basis weight of the long fiber nonwoven web was 40 g / m.2 And the basis weight of the natural fiber nonwoven web is 10 g / m2 Except that the basis weight was 50 g / m under the same conditions as in Example 23.2 Was obtained. Table 5 shows operability, physical properties of nonwoven fabric, and biodegradability.
[0096]
Example 26
Polybutylene succinate (PBS) having an MFR value of 40 g / 10 min, a melting point of 114 ° C. and a crystallization temperature of 75 ° C. is used as the high melting point polymer, and the MFR value is 30 g / 10 min. A copolymer of butylene succinate / ethylene succinate (BS / ES) = 85/15 (mol%) having a melting point of 102 ° C. and a crystallization temperature of 52 ° C. was used. On the other hand, as a crystal nucleating agent, a masterbatch containing 20% by weight of talc / titanium oxide = 1/1 (weight ratio) having an average particle size of 1.0 μm was prepared on the basis of a high melting point polymer and a low melting point polymer. This masterbatch is prepared in advance, and the masterbatch and the corresponding polymer are blended, respectively. The nucleating agent added to the high melting point component is 0.2% by weight, and the nucleating agent added to the low melting point component is 1.0% by weight. % As a raw material.
[0097]
The high melting point component and the low melting point component are melted at a spinning temperature of 180 ° C. using separate extruder-type melt extruders, and a single hole discharge amount of 1 is passed through a spinneret having a fiber cross section shown in FIG. The melt spinning was performed at a discharge ratio of 0.35 g / min and a high melting point component / low melting point component = 1/1 (weight ratio). After cooling the spun yarn with a known cooling device, the yarn was drawn and thinned at a drawing speed of 3500 m / min using an air sucker installed below the die, and was taken out. Next, the fiber is opened with a known fiber opening device, collected and deposited on a moving screen conveyor, and has a single-filament fineness of 3.5 denier (high-melting-point component segment fineness = 0.29 denier × 6, low-melting-point component). A nonwoven web composed of long fibers (segment fineness = 1.7 denier) was used. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m.2 Was obtained. The conditions of the thermal pressure welding were such that the shape of the pressure welding portion was round and the area thereof was 0.68 mm.2Sculpture pattern and 16 points / cm2 The processing temperature was set to 95 ° C. using an embossing roll provided with a pressed area ratio of 15% and a metal roll having a smooth surface. Table 6 shows the production conditions, operability, nonwoven fabric physical properties, and biodegradability.
[0098]
Examples 27 to 30
A long-fiber nonwoven fabric was obtained in the same manner as in Example 26, except that the addition amount of the crystal nucleating agent added to each component in Example 26 was changed as shown in Table 6. Table 6 shows the production conditions, operability, nonwoven fabric physical properties, and biodegradability.
[0099]
Example 31
As in Example 26, a copolymerized polyester of butylene succinate / ethylene succinate = 60/40 (mol%) having an MFR value of 20 g / 10 min, a melting point of 84 ° C., and a crystallization temperature of 20 ° C. was used as the low melting point component. Under the same conditions as in Example 26 except that the nucleating agent was added and the spinning temperature was set to 160 ° C., the multifilament type composite filament was melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn using an air sucker at a drawing speed of 3600 m / min, and was drawn. Next, the yarn is spread with a known spreader, and a single yarn fineness of 3.4 denier (high-melting-point component segment fineness = 0.28 denier × 6, low-melting-point component segment fineness = 1.7 denier) is placed on a moving screen conveyor. ) Was spread and deposited as a nonwoven web composed of the composite filaments. The operability is shown in Table 7.
[0101]
Example 32
As the high melting point polymer, a copolymer of butylene succinate / ethylene succinate (BS / ES) = 85/15 (mol%) having an MFR value of 30 g / 10 min, a melting point of 102 ° C. and a crystallization temperature of 52 ° C. And polycaprolactone having an MFR value of 30 g / 10 min, a melting point of 63 ° C. and a crystallization temperature of 23 ° C. was used as the low melting point polymer. On the other hand, as a crystal nucleating agent, a masterbatch containing 15% by weight of talc / titanium oxide = 1/1 (weight ratio) having an average particle size of 1.0 μm was prepared on the basis of a high melting point polymer and a low melting point polymer. The master batch was prepared in advance, and the masterbatch and the corresponding polymer were blended, and the nucleating agent added to the high melting point component was 0.6% by weight, and the nucleating agent added to the low melting point component was 3.0% by weight. % As a raw material.
[0102]
The high melting point component and the low melting point component are melted at a spinning temperature of 150 ° C. using a separate extruder-type melt extruder, and a single hole discharge amount of 2 is passed through a spinneret having a fiber cross section shown in FIG. The melt spinning was performed at a discharge ratio of high melting point component / low melting point component = 1.5 / 1 (weight ratio). The spun yarn was cooled by a known cooling device, and was then drawn and thinned at a drawing speed of 3800 m / min using an air soccer installed below the die. Next, the fiber is opened with a known fiber opening device, collected and deposited on a moving screen conveyor, and has a single yarn fineness of 4.7 denier (high melting point segment fineness = 0.47 denier × 6, low melting point component). A nonwoven web composed of long fibers (segment fineness = 1.9 denier) was used. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m.2 Was obtained. The conditions of the thermal pressure welding were such that the shape of the pressure welding portion was round and the area thereof was 0.68 mm.2 Sculpture pattern and 16 points / cm2 Using a hot embossing roll provided with a pressed area ratio of 15% and a metal roll having a smooth surface, the working temperature was 56 ° C. Table 7 shows the production conditions, operability, nonwoven fabric properties, and biodegradability.
[0103]
Comparative Example 1
A single-phase long fiber was melt-spun under the same conditions as in Example 1 except that the same high melting point component as in Example 1 was used alone and a spinneret having a single-phase fiber cross section was used. . After cooling the spun yarn with a known cooling device, the yarn was drawn down using an air sucker at a drawing speed of 4300 m / min, and was taken out. Next, the fiber was opened using a known opening device, and was spread and deposited on a moving screen conveyor as a long-fiber non-woven web composed of long fibers having a single-filament fineness of 4.0 denier. This long fiber non-woven web was hot-pressed with a hot-pressing device consisting of a hot embossing roll, and the basis weight was 30 g / m2.2 Was obtained. The thermal pressing conditions were the same as in Example 1 except that the processing temperature was 107 ° C. Table 8 shows the operability, non-woven fabric physical properties, and biodegradability.
[0104]
Comparative Example 2
A single-phase long fiber was melt-spun under the same conditions as in Example 1 except that the same low-melting point component as in Example 1 was used alone and a spinneret having a single-phase fiber cross section was used. . After cooling the spun yarn with a known cooling device, the yarn was drawn and thinned at a drawing speed of 4000 m / min using an air sucker, and was taken out. Next, the fiber was opened with a known opening device and spread and deposited on a moving screen conveyor as a long-fiber nonwoven web composed of long fibers having a single-filament fineness of 4.3 denier. The operability is shown in Table 8.
[0105]
Comparative Example 3
Under the same conditions as in Example 1, multi-leaf conjugated long fibers were melt-spun. After cooling the spun yarn with a known cooling device, the yarn was drawn with an air soccer at a drawing speed of 1800 m / min and drawn. Next, the fiber is opened by a known opening device, and the single yarn fineness is 9.5 denier (high melting point component fineness = 0.79 denier × 6, low melting point component fineness = 4.8 denier) on a moving screen conveyor. ) Was spread and deposited as a long-fiber non-woven web composed of the composite long fibers. Table 8 shows the operability, non-woven fabric physical properties, and biodegradability.
[0106]
Comparative Example 4
The same basis weight as in Example 23 was 25 g / m.2 Long fiber non-woven web with a basis weight of 25 g / m2 Laminated with a natural fiber non-woven web made of bleached cotton, heat-sealed with a hot embossing roll, and a basis weight of 50 g / m2 Was obtained. As for the conditions for the heat fusion processing, the roll has an engraved area of 0.4 cm2 The convex portion having a sculpture pattern was provided, the pressing area ratio of the convex portion was 15%, the linear pressure was 50 kg / cm, and the processing temperature was 95 ° C. Table 8 shows the physical properties and decomposition performance of the laminated nonwoven fabric.
[0107]
[Table 1]
[Table 2]
[Table 3]
[Table 4]
As is clear from Tables 1, 2, 3 and 4, in Example 1, polybutylene succinate was used as the high melting point component and butylene succinate / ethylene succinate copolymerized polyester was used as the low melting point component. Since the multi-leaf conjugate filaments of the present invention were applied, the spun yarn had good cooling properties, spinnability, and openability, and also had excellent mechanical performance. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0112]
In Example 2, the multi-leaf conjugated continuous fiber of the present invention using polybutylene succinate as the high melting point component and butylene succinate / butylene adipate copolymerized polyester as the low melting point component is applied, so that spinning is performed. The cooling property, spinnability, and fiber opening property of the yarn were good, and the mechanical performance was also excellent. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0113]
In Example 3, the multifilament type composite filament of the present invention using polybutylene succinate as the high melting point component and butylene succinate / butylene sebacate copolymerized polyester as the low melting point component was applied. The cooling property, spinnability, and openability of the spun yarn were good, and the mechanical performance was also excellent. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0114]
In Example 4, since the multi-leaf conjugated continuous fiber of the present invention using butylene succinate / ethylene succinate copolymerized polyester as both the high melting point component and the low melting point component is applied, the spun yarn is cooled. The properties, spinnability and openability were also good, and the mechanical properties were also excellent. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0115]
In Example 5, since the multilobal conjugate long fiber of the present invention using butylene succinate / ethylene succinate copolymerized polyester as the low melting point component was applied, the cooling property, spinnability and spun yarn of the spun yarn were applied. The spreadability was also good. Further, since the copolymerization ratio of butylene succinate as a low melting point component was higher than that of Example 1, the biodegradability was slightly inferior to that of Example 1 although the mechanical properties were particularly excellent.
[0116]
In Example 6, the multilobal bifilament of the present invention using butylene succinate / butylene adipate copolymerized polyester as the high melting point component and butylene succinate / ethylene succinate copolymerized polyester as the low melting point component was applied. As a result, the spun yarn had good cooling properties, spinnability and openability, and also had excellent mechanical properties. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0117]
In Example 7, the multilobal bifilament fiber of the present invention using butylene succinate / butylene sebacate copolymerized polyester as the high melting point component and butylene succinate / ethylene succinate copolymerized polyester as the low melting point component is applied. As a result, the spun yarn had good cooling properties, spinnability and openability, and also had excellent mechanical properties. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0118]
In Example 8, since the multi-leaf conjugated continuous fiber of the present invention using L-lactic acid as the high melting point component and L-lactic acid / ε-caprolactone copolymerized polyester as the low melting point component is applied, spinning is performed. The cooling property, spinnability, and fiber opening property of the yarn were good, and the mechanical performance was also excellent. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0119]
Example 9 shows that the multi-leaf conjugated filaments of the present invention were produced, despite the fact that the butylene succinate copolymerization ratio of butylene succinate / ethylene succinate copolymerized polyester used as the low melting point component was lower than that of Example 1. Because of the application, the spun yarn had good cooling properties, spinnability, and spreadability, and also had excellent mechanical performance. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0120]
Example 10 shows that the multi-leaf conjugated continuous fiber of the present invention was produced despite the fact that the butylene succinate copolymerization ratio of the butylene succinate / ethylene succinate copolymerized polyester used as the low melting point component was higher than that of Example 1. Because of the application, the spun yarn had good cooling properties, spinnability, and spreadability, and also had excellent mechanical performance. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0121]
In Example 11, since the multilobal conjugated filaments of the present invention were applied to both components even though a polymer having a higher viscosity than that of Example 1 was used, the cooling property of the spun yarn was slightly increased. Although inferior, the spinnability and the spreadability were good, and the mechanical performance was also excellent. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0122]
In Example 12, since the multilobal conjugated filaments of the present invention were applied to both components even though a polymer having lower viscosity than that of Example 1 was used, the cooling property of the spun yarn was high. The spinnability and openability were good, and the mechanical performance was also excellent. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0123]
Example 13 applied the multilobal conjugate long fiber of the present invention, despite the arrangement of the high melting point component, as shown in FIG. As a result, the cooling property, spinnability, and opening property of the spun yarn were good, and the mechanical performance was excellent although the strength was slightly lower than that of Example 1. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0124]
In Example 14, the number of protrusions of the high-melting component was smaller than that in Example 1, so that the peripheral ratio of the low-melting component was large, that is, the exposed portion of the low-melting component on the fiber surface was large. Since the multi-leaf conjugated filaments were used, the spun yarn was slightly inferior in cooling performance, but also excellent in spinnability and spreadability, and excellent in mechanical performance. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0125]
In Example 15, the number of protrusions of the high-melting point component was increased compared to Example 1, so that the low-melting-point component had a small circumference ratio, that is, despite the fact that the low-melting-point component had less exposed portions on the fiber surface, Since the multi-leaf composite filament is used, the biodegradability of the obtained nonwoven fabric is slightly inferior, but the spun yarn has good cooling, spinnability, and openability, and has good mechanical performance. Was also excellent.
[0126]
In Example 16, the low-melting point component was larger than that of Example 1, so that the peripheral ratio of the low-melting point component was large, that is, although the low melting point component had many exposed portions on the fiber surface, the multi-leaf type of the present invention was used. Since the composite filament was used, the spun yarn was slightly inferior in the cooling property, but had good spinnability and spreadability and excellent mechanical performance. Further, it was confirmed that this nonwoven fabric had better biodegradability than that of Example 1.
[0127]
In Example 17, the low-melting point component was reduced compared to Example 1, and therefore the low melting point component had a small circumference ratio, that is, despite the fact that the low melting point component had a small exposed portion on the fiber surface, the multi-leaf type of the present invention was used. Since the composite filaments are used, the obtained nonwoven fabric has a slightly poor biodegradability, but the spun yarn has good cooling, spinnability and openability, and also has excellent mechanical performance. Was something.
[0128]
In Example 18, since the low melting point component was further increased than in Example 16, the circumference ratio of the low melting point component was large, that is, the exposed portion of the low melting point component on the fiber surface was increased, and the cooling property of the spun yarn was reduced. Inferior and not very favorable in terms of operability.
[0129]
In Example 19, since the low melting point component was further reduced as compared with Example 17, the circumference ratio of the low melting point component was small, that is, the exposed portion of the low melting point component on the fiber surface was reduced. Although the performance was slightly inferior, the spun yarn had good cooling properties, spinnability and spreadability, and also had excellent mechanical performance.
[0130]
In Example 20, although the pulling speed of the spun yarn was lower than that of Example 1, the multifilament type composite filament of the present invention was applied. Was excellent in cooling performance, spinnability and spreadability, and also excellent in mechanical performance. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0131]
In Example 21, since the long-fiber nonwoven web obtained in Example 1 was hot-pressed using an ultrasonic welding device, the obtained non-woven fabric was excellent in flexibility and spun yarn. The cooling property, spinnability, and opening property were also good, and the mechanical performance was also excellent. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0132]
In Example 22, although the processing temperature in the hot pressing step was higher than that in Example 1, the multi-leaf conjugate filaments of the present invention were applied. Although slightly inferior, the spun yarn had good cooling properties, spinnability, and spreadability, and also had excellent mechanical performance. In addition, it was confirmed that this nonwoven fabric had good biodegradability.
[0133]
[Table 5]
As is clear from Table 5, Example 23 is a biodegradable nonwoven fabric of the present invention in which a nonwoven web made of natural fibers is laminated. Since the composite filament has excellent mechanical properties and has a biodegradation rate comparable to that of natural fiber, it was confirmed that the nonwoven fabric was excellent in biodegradability even as a laminated nonwoven fabric.
[0135]
In Example 24, since the lamination ratio of the natural fiber nonwoven web was larger than that in Example 23, the obtained nonwoven fabric was further excellent in water absorption, and the composite filament had a biodegradation rate similar to that of the natural fiber. Therefore, the biodegradability was also excellent. In addition, the strength of the nonwoven fabric was somewhat low due to the small number of long fiber nonwoven webs, but it had practical mechanical properties.
[0136]
In Example 25, the lamination ratio of the natural fiber nonwoven web was smaller than that in Example 23, so that the water absorption was slightly inferior, but the laminated nonwoven fabric had practical mechanical properties. Since it had the same biodegradation rate, it had excellent biodegradation performance.
[0137]
[Table 6]
[Table 7]
As is clear from Tables 6 and 7, in Examples 26 to 28, the operability was good without any problem in the cooling property and the spreadability of the spun yarn, and the performance of the obtained nonwoven fabric was good. Was practically powerful, flexible and biodegradable.
[0140]
In Example 29, since the amount of the crystal nucleating agent added was the same in the high melting point component and the low melting point component, the cooling property of the spun yarn was slightly lowered, but there was no particular problem in the operability.
[0141]
In Example 30, since the total amount of the crystal nucleating agent was too much larger than the preferred range of the present invention, there was no problem in the cooling property and the spreading property of the spun yarn, but the strength of the obtained nonwoven fabric was high. Was slightly inferior to Example 26.
[0142]
In Example 31, since the polymer having a lower melting point was used as the low melting point component, the effect of the crystal nucleating agent greatly contributed, but the cooling and opening properties of the spun yarn were slightly inferior. .
[0144]
Example 32In the above, a polymer having a low melting point was used for both components, but it was found that there was no problem in the cooling property and openability of the spun yarn because the effect of the crystal nucleating agent greatly contributed.
[0145]
[Table 8]
In contrast, as is clear from Table 8, Comparative Example 1 uses the same high-melting point component as in Example 1, but is a single-phase type having a fiber cross-section outside the scope of the present invention. Although the spun yarn had good cooling properties, spinnability, and openability, and excellent mechanical performance, the obtained nonwoven fabric had poor biodegradability.
[0147]
Comparative Example 2 used the same low-melting point component as in Example 1, but because the fiber cross section was a single-phase type outside the scope of the present invention, the cooling property, spinnability, and The spreadability was poor, and the target nonwoven fabric could not be obtained.
[0148]
In Comparative Example 3, since the drawing speed of the spun yarn was low and out of the range of the present invention, the spun yarn was inferior in cooling property, spinnability and openability, and the obtained nonwoven fabric was mechanically It was inferior in performance and dimensional stability.
[0149]
Comparative Example 4 is a laminated nonwoven fabric of a natural fiber nonwoven web and a long fiber nonwoven web. However, since the integration of the two webs was performed by a hot pressing device consisting of a hot embossing roll, the natural fiber nonwoven web was It was taken up by a roller and could not be fixed by heat pressure welding, and a laminated nonwoven fabric in which a natural fiber nonwoven web and a long fiber nonwoven web were integrated could not be obtained.
[0150]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the biodegradable nonwoven fabric which is excellent in the cooling property and opening property of a spun yarn, and whose biodegradability is controllable, the mechanical properties and texture of a nonwoven fabric are excellent, and the heat bonding function is further provided. And a method for manufacturing the same.
[0151]
The nonwoven fabric of the present invention includes diapers, sanitary products and other medical and sanitary materials, wiping cloths such as disposable towels and wiping cloths, disposable packaging materials, household garbage collection bags and other waste treatment materials. It is suitable as a material for daily life or as a material for industrial materials typified by agriculture, horticulture and civil engineering. Moreover, since this nonwoven fabric has biodegradability, it completely decomposes and disappears after its use, which is beneficial from the viewpoint of protecting the natural environment, or it can be reused, for example, by composting it into fertilizer. Therefore, it is also beneficial from the viewpoint of resource reuse.
[Brief description of the drawings]
FIG. 1 is a model diagram of a fiber cross section of a multilobal conjugate long fiber of the present invention.
FIG. 2 is a model diagram of a fiber cross section of the multilobal conjugate long fiber of the present invention.
FIG. 3 is a model diagram of a fiber cross section of the multilobal conjugate long fiber of the present invention.
[Explanation of symbols]
1 High melting point component
2 Low melting point components
3 center
Claims (20)
［（ΔＴＡ ＋ΔＴＢ）／１００］−２ ／３ ≦ＱＡ ＋ＱＢ ≦［（ΔＴＡ ＋ΔＴＢ）／１００］＋４…（１）
ＱＡ ≦ＱＢ …（２）
但し、ΔＴＡ ＝高融点成分の融点−高融点成分の結晶化温度≧３５
ΔＴＢ ＝低融点成分の融点−低融点成分の結晶化温度≧３５When the amount of the nucleating agent added to the high melting point component is QA (% by weight) and the amount of the nucleating agent added to the low melting point component is QB (% by weight), (1) The biodegradable non-woven fabric according to claim 8, wherein the non-woven fabric is added so as to satisfy the formulas (2) and (2).
[(ΔTA + ΔTB) / 100] −2 / 3 ≦ QA + QB ≦ [(ΔTA + ΔTB) / 100] +4 (1)
QA ≦ QB (2)
Where ΔTA = melting point of high melting point component−crystallization temperature of high melting point component ≧ 35
ΔTB = melting point of low melting point component−crystallization temperature of low melting point component ≧ 35
［（ΔＴＡ ＋ΔＴＢ）／１００］−２ ／３ ≦ＱＡ ＋ＱＢ ≦［（ΔＴＡ ＋ΔＴＢ）／１００］＋４…（１）
ＱＡ ≦ＱＢ …（２）
但し、ΔＴＡ ＝高融点成分の融点−高融点成分の結晶化温度≧３５
ΔＴＢ ＝低融点成分の融点−低融点成分の結晶化温度≧３５When the amount of the crystal nucleating agent added to the high melting point component is QA (% by weight) and the amount of the nucleating agent added to the low melting point component is QB (% by weight), the equations (1) and (2) 20. The method for producing a biodegradable nonwoven fabric according to claim 19, wherein a nucleating agent is added so as to satisfy the formula.
[(ΔTA + ΔTB) / 100] −2 / 3 ≦ QA + QB ≦ [(ΔTA + ΔTB) / 100] +4 (1)
QA ≦ QB (2)
Where ΔTA = melting point of high melting point component−crystallization temperature of high melting point component ≧ 35
ΔTB = melting point of low melting point component−crystallization temperature of low melting point component ≧ 35
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05111596A JP3553722B2 (en) | 1995-03-08 | 1996-03-08 | Biodegradable nonwoven fabric and method for producing the same |
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4768095 | 1995-03-08 | ||
| JP7-47680 | 1995-07-12 | ||
| JP7-175296 | 1995-07-12 | ||
| JP17529695 | 1995-07-12 | ||
| JP05111596A JP3553722B2 (en) | 1995-03-08 | 1996-03-08 | Biodegradable nonwoven fabric and method for producing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0978427A JPH0978427A (en) | 1997-03-25 |
| JP3553722B2 true JP3553722B2 (en) | 2004-08-11 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP05111596A Expired - Fee Related JP3553722B2 (en) | 1995-03-08 | 1996-03-08 | Biodegradable nonwoven fabric and method for producing the same |
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| JP (1) | JP3553722B2 (en) |
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| KR102104135B1 (en) * | 2013-07-12 | 2020-04-23 | 쓰리엠 이노베이티브 프로퍼티즈 캄파니 | Scouring Pad for Washing Dishes |
| US20150330003A1 (en) * | 2014-05-13 | 2015-11-19 | First Quality Nonwovens, Inc. | Patterned nonwoven and method of making the same using a through-air drying process |
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1996
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| JPH0978427A (en) | 1997-03-25 |
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