JP2004197232A - Leathery sheetlike material and method for producing the same - Google Patents
Leathery sheetlike material and method for producing the same Download PDFInfo
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- JP2004197232A JP2004197232A JP2002363495A JP2002363495A JP2004197232A JP 2004197232 A JP2004197232 A JP 2004197232A JP 2002363495 A JP2002363495 A JP 2002363495A JP 2002363495 A JP2002363495 A JP 2002363495A JP 2004197232 A JP2004197232 A JP 2004197232A
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Landscapes
- Synthetic Leather, Interior Materials Or Flexible Sheet Materials (AREA)
Abstract
Description
【０００１】
【発明の属する技術分野】
本発明は、皮革様シート状物およびその製造方法に関するものである。さらに詳しくは伸び止め感が強いにもかかわらず、ソフトでかつ低反発である天然皮革の物性に類似した人工の皮革様シート状物およびその製造方法に関するものである。
【０００２】
【従来の技術】
天然皮革の代替物として、繊維と高分子弾性体を用いたいわゆる人工皮革と呼ばれる皮革様シート状物が広く用いられている。だが、人工皮革は天然皮革に比べて物性面の優位性は比較的得られているものの、外観や風合面では高級な天然皮革のレベルに至っていないのが実情であった。そして外観においては、それを解決するために様々な仕上げ方法等が研究され、天然皮革に類似した物やさらには天然皮革では表すことが出来なかった外観が数多く提案されてきている。しかし風合い面においては様々な研究がなされ非常に柔らかな物も提案されてきてはいるものの、優れた天然皮革の持つ特性である低反発でくたくた感のある非常に柔らかな物は未だ得られていない。
【０００３】
例えば特許第３１５５１３５号では、少なくとも２種類の高分子重合体からなる極細化可能な複合繊維からウェブを形成し、該ウェブの厚さ方向にニードルパンチングを施して、絡合繊維質基材を作成し、該絡合繊維質基材に高分子弾性体を含浸、凝固させ、その後、該絡合繊維質基材を構成する複合繊維を極細化する方法が開示されている。しかしこのような方法で得られた皮革様シート状物は柔らかな物ではあるものの、含浸された高分子弾性体の特性から反発感のあるゴムライクな風合いとなり、天然皮革が有する優れた風合いである、低反発でくたくた感のある非常に柔らかな風合いを持つシート状物は実現することができなかった。
【０００４】
【特許文献１】
特許第３１５５１３５号公報
【０００５】
【発明が解決しようとする課題】
本発明の目的は、これら従来の皮革様シート状物では持ち得なかった伸び止め感が強いにもかかわらず、ソフトでかつ低反発である天然皮革の物性に類似した人工の皮革様シート状物およびその製造方法を提供することである。
【０００６】
【課題を解決するための手段】
本発明の皮革様シート状物は、極細繊維と高分子弾性体からなるシート状物であって、高分子弾性体が一方の面から２５μｍ以上の深さまで存在する含浸層と、高分子弾性体が存在しない未含浸層があり、含浸層内では極細繊維が繊維束状態で存在し、高分子弾性体が該繊維束の外周を包囲しているが、繊維束の内部には高分子弾性体が存在していないことを特徴とする。さらに含浸層の厚さが２５〜３００μｍであることや、未含浸層部分の目付が３０〜５００ｇ／ｍ2であること、含浸層の高分子弾性体が、充実型または独立多孔型であること、折り曲げ回復率が、７５％以下であることが好ましい。
【０００７】
また、本発明の皮革様シート状物の製造方法の第一は、溶剤溶解性の異なる２つ以上の成分からなる極細繊維形成性の海島繊維からなるシート上に、含浸層と未含浸層が発生するように高分子弾性体溶液を一方の表面から塗布し凝固させ、次いで海島繊維の海成分を溶解する溶剤を用いて繊維の海成分を除去することを特徴とする。
【０００８】
そして、もうひとつの本発明である、皮革様シート状物の製造方法の第二は、溶剤溶解性の異なる２つ以上の成分からなる極細繊維形成性の海島繊維からなるシート上に、中心部に未含浸層が発生するように高分子弾性体溶液を両方の表面からそれぞれ塗布し凝固させ含浸層とし、次いで海島繊維の海成分を溶解する溶剤を用いて繊維の海成分を除去し、その後未含浸層部分でスライスして２分割することを特徴とする。
【０００９】
さらには、本発明の製造方法では、高分子弾性体溶液の塗布前に、海島繊維を構成する海成分の軟化温度以上、島成分の軟化温度未満で、あらかじめ海島繊維からなるシート表面をプレスすることや、高分子弾性体溶液の凝固方法が乾式法であることが好ましい。
【００１０】
【発明の実施の形態】
本発明は、極細繊維と高分子弾性体とからなるシート状物であって、高分子弾性体が存在する含浸層と存在しない未含浸層がある皮革様シート状物に関するものである。
【００１１】
本発明における極細繊維とは、０．２ｄｔｅｘ以下、好ましくは０．１ｄｔｅｘ以下、特に好ましくは０．０００１〜０．０５ｄｔｅｘの繊度の極細繊維のことである。また、そのような極細繊維の例としては、ポリエチレンテレフタレートやポリブチレンテレフタレートなどのポリエステル繊維、ナイロン６、ナイロン６６、ナイロン１２などのポリアミド繊維を挙げることができる。さらに本発明ではこの極細繊維が束として集合している極細収束繊維が存在していることが必要である。例えばこのような極細集束繊維としては、溶剤溶解性の異なる２成分以上の重合体組成物から複合紡糸法、混合紡糸法などにより海島型繊維として紡糸して得た多成分繊維の少なくとも一成分を除去し極細化した繊維等が挙げられる。ただし該極細繊維は、束状になっている場合、一つの束に極細繊維が好ましくは、１０本から５０００本、更に好ましくは、１００本から２０００本含まれていることが好ましい。
【００１２】
本発明のシート状物は極細繊維と高分子弾性体からなるものであるが、上記のような極細繊維を主とするシート状物であれば特に制限はなく、繊維全部が極細繊維ではなく一部に極細繊維を含むものでも良い。このような基体としては織編物であっても良いが、風合を向上させるためには不織布が主体であり、織編物は補強用として一部に含むか、全く含まないことが好ましい。
【００１３】
さらに、本発明の皮革様シート状物で用いられる高分子弾性体としては、ポリウレタン樹脂エラストマー、ポリウレアエラストマー、ポリウレタン樹脂・ポリウレアエラストマー、ポリアクリル酸樹脂、アクリロニトリル・ブタジエンエラストマー、スチレン・ブタジエンエラストマー等が挙げられるが、なかでもポリウレタン樹脂エラストマー、ポリウレアエラストマー、ポリウレタン樹脂・ポリウレアエラストマー等のポリウレタン樹脂系高分子が好ましい。
【００１４】
この含浸層に存在する高分子弾性体の１００％伸長モジュラスは、２００〜５０００Ｎ／ｃｍ2であることが好ましく、更に好ましくは、３００〜４０００Ｎ／ｃｍ2であり、特に好ましくは、４００〜３０００Ｎ／ｃｍ2である。１００％伸長モジュラスが、２００Ｎ／ｃｍ2未満の場合には得られた基体は柔軟性に富むが、耐熱性、耐溶剤性等が減少する傾向にある。逆に５０００Ｎ／ｃｍ2を越える場合には得られた基体の風合いが硬くなる傾向にある。高分子弾性体の１００％伸長モジュラスを好ましい範囲に調整する方法としては、例えばポリウレタン樹脂エラストマーを用いる場合、ポリマー中の有機ジイソシアネート含有量と鎖伸長剤量を調整することによって容易に行うことができる。
【００１５】
また、この含浸層の高分子弾性体は、充実型または独立多孔型であることが好ましい。湿式凝固法などによって得られる連続多孔質の場合には、得られた皮革様シート状物の伸び止め効果が減少する傾向にある。
【００１６】
本発明の皮革様シート状物は、高分子弾性体が一方の面から２５μｍ以上の深さまで存在する含浸層と、高分子弾性体が存在しない未含浸層の両方が存在するものであるが、さらにはこの含浸層の厚さは、２５〜３００μｍであることが好ましく、さらには５０〜２５０μｍ、もっとも好ましくは７５〜２００μｍの厚さであることが好ましい。このとき高分子弾性体の存在する層が薄くなると得られるシート状物の強度が弱くなり、さらに加工中の伸び止め性も低下し、縦方向に伸びてしまう等の傾向にある。一方層が厚くなると強く腰のある風合いにはなるが、堅くなる傾向にある。特に伸び止め性に優れている含浸層の高分子弾性体が充実型や独立多孔型の場合には、連続多孔の高分子弾性体を用いている場合よりも堅くなる傾向にあるので、含浸層はより薄くする必要がある。
【００１７】
また、この含浸層における繊維と高分子弾性体の比率は、５：９５〜９５：５の範囲であることが好ましく、更に好ましくは１０：９０〜５０：５０、特に好ましくは１５：８５〜４０：６０の範囲であることが好ましい。このとき高分子弾性体の比率が少ないと、得られるシート状物の強度が弱くなる傾向にある。一方含浸層における高分子弾性体の比率が多いと、得られるシート状物の風合いは堅くなる。特に高分子弾性体が充実型の場合には、その特性から反発性の強いシート状物となる傾向にある。
【００１８】
本発明の皮革様シート状物は、繊維のみからなる高分子弾性体の存在しない未含浸層が存在することが必要である。本発明では、未含浸部が存在することによって、表裏の応力の分布に勾配ができ、バランスが良くなって低反発で非常に風合いの良い物が得られる。さらにはその未含浸部の繊維目付は３０〜５００ｇ／ｍ2の範囲にあることが好ましく、もっと好ましくは４０〜４００ｇ／ｍ2の範囲であり、特には、５０〜３００ｇ／ｍ2の範囲であることが好ましい。未含浸部の目付が低くなると、未含浸部の存在しない従来の皮革様シート状物とほぼ同様の特性となり、伸び止め性とソフト性を両立させることが困難な傾向にある。一方、未含浸部が多くなりすぎると未含浸の不織布と差が少なくなり伸び止め性が低下する傾向にある。
【００１９】
本発明の皮革様シート状物は、上記のような含浸層と未含浸層からなるものであるが、本発明の最も特徴的な点は、含浸層内では極細繊維が繊維束状態で存在し、含浸層を構成する高分子弾性体が該繊維束の外周を包囲してはいるが、繊維束の内部には高分子弾性体が存在していないことである。
【００２０】
本発明と異なり、含浸層内に極細繊維が繊維束ではなくそのまま極細単繊維の状態で侵入している場合には、極細単繊維が高分子弾性体間に密に存在し、極細単繊維に補強された高分子弾性体が硬く変形しにくいものとなりやすい。また、たとえ繊維と高分子弾性体を何らかの手段で非接合化したとしても、極細単繊維の状態で侵入している場合には、極細繊維と高分子弾性体の距離が短く繊維の自由度が低くなり、どうしても固い構造物である層が形成される傾向にある。それに比して極細繊維が繊維束で存在する場合には、繊維束内の繊維密度が高くなる分全体の繊維目付に比して繊維間空隙が大きくなり、高分子弾性体が大きな塊で存在し、弾性体としての性質が強く引き出され、変形しやすくなる。また、本発明では高分子弾性体は繊維束を包囲して、繊維束内部に高分子弾性体が存在しないので、極細繊維と高分子弾性体間の距離が大きく、繊維の自由度が大きくより柔軟な構造物となり、柔軟な風合を実現できるのである。
【００２１】
本発明では、高分子弾性体が繊維束を包囲しているので、シート状物の小変形時には高分子弾性体のみが変形し小さな応力だけが発生するが、さらなる変形時には補強繊維である繊維束に変形が伝達され、大きな応力が発生する。このような現象が発生するためには、繊維束が高分子弾性体に充分に囲まれていることが必要であり、できればその断面がほぼ円形であることが好ましい。例えば繊維束の周辺の高分子弾性体に割れ目が存在していたり、その繊維束周囲の空間に、繊維束への応力が伝わりにくい部分、方向が存在すると、シート状物が大変形した時のみしか繊維と高分子弾性体の複合効果が発生しないので好ましくない。
【００２２】
さらには繊維束を包囲している高分子弾性体の空隙空間を、極細繊維が体積にして２０〜８０％占めていることが好ましく、さらには３０〜７０％、最も好ましくは４０〜６０％を占めている状態が好ましい。繊維束周辺の空隙空間が大きすぎると繊維束への応力が伝わりにくく、伸び止め感の低いものとなる傾向にあり、逆に空隙空間が小さすぎると硬くなる傾向にある。高分子弾性体がこのような構造をとるためには、極細繊維と高分子弾性体からなる含浸層は、充実層であることや、または空隙が連続していない独立多孔構造をとることが好ましい。
【００２３】
本発明の皮革様シート状物は、その構造から非常にソフトで低反発なものである。ここで、低反発感の代用特性である折り曲げ回復率は、７５％以下であることが好ましく、さらには６０％以下、もっとも好ましくは５５％以下であることが望ましい。折り曲げ回復率は、幅１ｃｍのサンプルを含浸層を下側にして置き、端１ｃｍを１８０°折り曲げ、荷重９．８Ｎをかけた状態で１時間放置し、荷重を取り除いた後３０秒後の回復率を、１８０°を１００％として示したものであり、折れたままの状態の場合を０％とする。この折り曲げ回復率の値が小さいほど、反発感のないくたくたな柔らかさであることを示している。
【００２４】
また、本発明の皮革様シート状物は、その表面が銀付調や立毛を有するスエード調やヌバック調であることも好ましい。ここで銀付調である皮革様シート状物とは、含浸層がシート状物の一方の側に偏在し、その偏在した側の表面が銀付調であるものであり、立毛を有する皮革様シート状物とは、含浸層がシート状物の一方の側に偏在し、その偏在した側の最表面が極細繊維立毛を有しているものである。
【００２５】
このような本発明の皮革様シート状物は、別の本発明である皮革様シート状物の製造方法によって得ることができる。すなわち、溶剤溶解性の異なる２つ以上の成分からなる極細繊維形成性の海島繊維からなるシート上に、含浸層と未含浸層が発生するように高分子弾性体溶液を一方の表面から塗布し凝固させ、次いで海島繊維の海成分を溶解する溶剤を用いて繊維の海成分を除去する方法や、または溶剤溶解性の異なる２つ以上の成分からなる極細繊維形成性の海島繊維からなるシート上に、中心部に未含浸層が発生するように高分子弾性体溶液を両方の表面からそれぞれ塗布し凝固させ含浸層とし、次いで海島繊維の海成分を溶解する溶剤を用いて繊維の海成分を除去し、その後未含浸層部分でスライスして２分割する方法である。
【００２６】
このようにすることにより、含浸層を構成する極細繊維が繊維束状態で存在し、含浸層を構成する高分子弾性体が該繊維束を包囲してはいるが、繊維束内部に高分子弾性体が存在していないソフトで低反発な皮革様シート状物を製造することができる。
【００２７】
本発明の溶剤溶解性の異なる２つ以上の成分からなる極細繊維形成性の海島繊維としては、例えば具体的には、溶剤溶解性の異なる２成分以上の重合体組成物から複合紡糸法、混合紡糸法などにより紡糸し、海島型繊維としたものである。このとき島成分の繊度は特に規定する必要はないが、好ましくは、０．２ｄｔｅｘ以下、さらに好ましくは、０．１ｄｔｅｘ以下、特に好ましくは、０．０００１〜０．０５ｄｔｅｘの繊度であることが好ましい。
【００２８】
また、そのような溶剤溶解性の異なる２成分以上の重合体組成物の好ましい組み合わせとしては、不溶解成分としてポリエチレンテレフタレートやポリブチレンテレフタレートなどのポリエステルを選定したときには易溶解成分としてポリエチレン、ポリプロピレン、ポリスチレンなどのポリオレフィン類が、不溶解成分としてナイロン６、ナイロン６６、ナイロン１２などのポリアミドを選定した時には易溶解成分としてポリエステル類、ポリオレフィン類が好ましく選定される。
【００２９】
本発明で用いるこのような極細繊維形成性の海島繊維からなるシートとしては、シート状であれば特に制限されるものではなく、各種織編物や不織布のいずれでもよいが、風合面から不織布をベースとするものであることが好ましい。例えば繊維を不織布化するには、公知のカード、レーヤー、ニードルロッカー、流体絡合装置などを用いることができ、交絡繊維密度の高い緻密に３次元絡合した不織布を得ることができる。
【００３０】
さらに、ここで得られた該絡合繊維質シートを高分子弾性体溶液の塗布前に、海島繊維を構成する海成分の軟化温度以上、島成分の軟化温度未満で、あらかじめ海島繊維からなるシート表面をプレスすることで厚みと表面を整える事が好ましい。ここで厚みを整えることで最終的に得られる製品の厚みをコントロールすることができる。さらに、表面を整える事で製品面の平滑性をコントロールすることもできる。加熱と加圧の条件を調整することにより、高分子弾性体溶液の浸透度合いを調整するのである。整えられた面が融着などで膜などを形成する場合、付与される高分子弾性体はほとんど浸透されず、一方融着などで膜などができず最表面の繊維密度も低い場合、高分子弾性体溶液はよく浸透される。
【００３１】
本発明では、このようにして得られた極細繊維形成性の海島繊維を含む基材の一方の整えられた面から２５〜３００μｍの範囲に、該海島繊維を空隙無く包囲する高分子弾性体を含む含浸層を形成することが必要である。例えば基材への高分子弾性体溶液の浸透度合いを調整するなどの方法で含浸層の厚さを調整する。
【００３２】
また、ここで付与された高分子弾性体は、一部に気泡などの独立発泡が繊維の周辺に存在することは構わないが、基本的に海島繊維と高分子弾性体には空隙が無いことが好ましい。空隙があった場合には、最終的に高分子弾性体が極細繊維束の外周をうまく包囲することができない。さらには繊維と高分子弾性体間には空隙が無いことに加えて接着もしていないことが好ましい。
【００３３】
このような含浸層を成形するためには、高分子弾性体溶液の凝固方法が乾式法であることが好ましく、例えば繊維質基材の一方の面から高分子弾性体の有機溶剤溶液または分散液（水性エマルジョンを含む）を塗布し、基材中に充分しみこませた後、加熱乾燥により凝固させることが好ましい。さらに含浸深さを調整するために塗布回数は１回ではなく、複数回、例えば２〜５回に分けて塗布、乾燥を繰り返し行うことにより、より表層に近い部分の高分子弾性体の含浸量を高くすることができ、風合いを向上させることができる。
【００３４】
このとき塗布させる高分子弾性体液の固型分濃度は、５〜５０％であることが好ましい。さらには、７〜３０％であることがより好ましく、もっとも好ましくは１０〜２０％であることが望ましい。５％以下の濃度だと高分子弾性体溶液の粘度が低すぎて基材中へ浸透しすぎたり基材表面を流れてうまく均一に浸透させることができなかったりと加工上困難である上に、うまく付与できた場合もその含浸層は、基材の一方の面から２５μｍ以下となることが多い。一方高濃度になるほど高分子弾性体溶液の粘度が高くなる傾向があり、基材への浸透度合いのバランスが崩れやすく、均一に高分子弾性体を付与することが困難となる傾向にある。特に固型分濃度が高すぎると付与される高分子弾性体量が多くなりすぎ反発感のある腰のある風合いとなりやすく、本発明の目標とするソフトで低反発な素材とは異なるものとなってしまう傾向にある。
【００３５】
さらに、ここで付与される高分子弾性体溶液の粘度とその表面張力によってその基材への浸透度合いを調整することができる。高分子弾性体の粘度は、その濃度を調整するほかに一般的な増粘剤を用いることもできる。また、高分子弾性体溶液の表面張力をコントロールするにはその溶液中に種々の添加剤を用いることで調整することができる。
【００３６】
さらに本発明では、その含浸層の偏在した側の表面に皮革様として適した外観とすることが好ましく、表皮層の形成方法としては、公知のいずれの方法を用いることもできる。
【００３７】
本発明の製造方法では、次いで海島繊維の海成分を溶解する溶剤を用いて、その海成分を除去する。この溶剤は、極細繊維の島成分を溶解しないことが必要であり、含浸層に用いられている高分子弾性体を少量なら溶解しても良いが、できれば溶解しないことが好ましい。このように海島型繊維の海成分を除去することにより、含浸層において高分子弾性体が島成分の極細繊維とは非接合状態となる構造が形成される。より具体的には、例えば島成分にナイロンを、海成分にポリエチレンを用いた場合には、トルエンを用いることが好ましい。抽出効率を高めるために加熱した溶剤を用いるのも好ましい方法である。
【００３８】
さらに、本発明の製造方法においては、溶剤溶解性の異なる２つ以上の成分からなる極細繊維形成性の海島繊維を含む基材に、該海島繊維を空隙無く包囲する該高分子弾性体からなる含浸層を基材の両方の面から２５〜３００μｍの範囲に形成し、次いで海島繊維の海成分を溶解する溶剤を用いて海成分を除去した後、その厚みの中央部分でスライスする方法についても提案している。
【００３９】
このようにすることにより、高い生産性が得られるとともに、薄地の加工において安定した高い加工性が得られる。本発明品の薄地の製造において片側のみ使用して作成する方法では海島繊維の海成分を溶解する溶剤を用いて海成分を除去する工程においてその基材の柔らかさから皺が発生したり、機械張力で伸びてしまったりと加工性に問題が生じ易い傾向があった。両面に樹脂を付与したものはしっかりしておりその加工は安定しており、とても容易なものとなる。さらに両面含浸では、工程途中のロール表面に接する未含浸部が存在しないために、それによる毛羽等の発生が少なく、工程安定性が高くなる傾向にある。
【００４０】
ここで得られた皮革様シート状物の一つとして立毛タイプの外観を持つ物は、さらに、その含浸層の存在する表面に高分子弾性体をグラビア処理したり、バフィングを行うことにより起毛加工を施し、必要に応じて染色、柔軟剤付与、揉み加工することができる。
【００４１】
一方、得られた皮革様シート状物のもう一つとして銀面タイプの外観を持つ物は、さらに、その含浸層の存在する表面に皮革様として適した外観をもった高分子弾性体の表皮層を付与することで作成できる。表皮層の形成方法としては、公知のいずれの方法を用いることもでき、例えば高分子弾性体からなる溶液や分散液を、基材上にラミネートあるいはコーティングすることにより銀付調である表皮層とすることができる。さらにこのようにして得られた銀付調の表面に必要に応じて高分子弾性体をグラビア処理したり、エンボス処理したりし、最表面をさらに整えることも好ましい。
【００４２】
また、本発明の製造方法では、このようにして得られた基材に揉み加工を施すことも好ましい。揉み加工の方法としては、例えばシート状物をクランプに把持し、一方のクランプをシートに揉み変形が加わるように駆動させる方法、あるいは２つの組み合わさった突起を有するステーの間にシート状物を通しシート状物に突起を押し込みながら揉みほぐしを行う方法等が挙げられる。
【００４３】
このようにして得られた本発明の皮革様シート状物は、従来の皮革様シート状物では持ち得なかった天然皮革の持つ特徴である伸び止め感の強さと低反発でくたくた感のある非常に柔らかな風合いを有する物となる。
【００４４】
【実施例】
以下、実施例により本発明をさらに説明するが、本発明はこれらにより制限されるものではない。実施例で特段断りのない限りパーセント（％）、比率は重量％、または重量比率を示す。実施例における測定値はそれぞれ以下の方法によったものである。
【００４５】
（１）１００％伸長応力
樹脂フィルム（厚さ約０．１ｍｍ）より採取したテストピースを、恒速伸長試験器で１００％／ｍｉｎにて伸長試験し、１００％伸長時点の荷重を読み取りＮ／ｃｍ2単位に換算する。テストピースはＪＩＳ−Ｋ−６３０１−２号型ダンベル法に準拠する。
【００４６】
（２）含浸層深さ
基材の断面電顕写真より測定し、平均値を採用する。
【００４７】
（３）厚さ
スプリング式ダイアルゲージ（荷重１．１８Ｎ／ｃｍ2）にて測定する。
【００４８】
（４）重量
１０ｃｍ×１０ｃｍに切断した試験片を、精密天秤にて測定する。
【００４９】
（５）σ５／σ２０／引張強力／伸び
皮革様シート状物から採取したテストピースを、恒速伸長試験器で伸長試験し５％、２０％伸長時と破断時の荷重の値で示す。また、破断時の伸びも測定する。テストピースはＪＩＳ−Ｋ−６５５０ ５−２−１に準拠する。
【００５０】
（６）引裂
皮革様シート状物から採取したテストピースに切り込みを入れ、恒速伸長試験器で伸長試験し引裂時の荷重の変化を平均値で示す。
【００５１】
（７）剥離強力
幅２．５ｃｍ×長さ１５ｃｍのテストピースの銀面層側に、同じサイズの平織り布をはりあわせたＰＶＣシートをウレタン系接着剤で接着する。このテストピースに２ｃｍ間隔で５区間の印をつけ、恒速引張試験器で５０ｍｍ／ｍｉｎの速度で剥離試験を行う。この時の剥離強力を記録計に記し２ｃｍ間隔の５区間のそれぞれの部分の最小値を読み、その５点の平均値を幅１ｃｍあたりに換算して表示する。
【００５２】
（８）摩耗
テーバー摩耗試験器にて摩耗輪＃２８０荷重９．８Nにて１００回摩耗時の重量変化（ｍｇ）を測定する。
【００５３】
（９）未含浸層部分の目付け
抽出前の含浸基材の全体の厚さａから（２）の含浸層深さｂを引き、その値を全体の厚さａで除して、未含浸層部分の比率を計算し、それに抽出後の繊維目付け（抽出前の目付け×未抽出繊維の構成比）ｃを掛けて算出する。
（未含浸層部分の目付け）＝（（ａ−ｂ）／ａ）×ｃ
【００５４】
（１０）含浸層部分の繊維の目付け
抽出前の含浸基材の全体の厚さａで、（２）の含浸層深さｂを除して、含浸層部分の比率を計算し、それに抽出後の繊維目付け（抽出前の目付け×未抽出繊維の構成比）ｃを掛けて、含浸層部分の繊維目付けを算出する。
（含浸層部分の繊維目付け）＝（ｂ／ａ）×ｃ
【００５５】
（１１）含浸層部分の高分子弾性体の目付け
次に高分子弾性体の含浸溶液濃度に塗布した溶液目付けを掛けて、含浸層部分の高分子弾性体目付けを算出する。
【００５６】
（１２）外観
表中の「外観」は以下の評価をする。
◎：優れている 〇：良い △：普通 ×：悪い
【００５７】
（１３）挫屈感
表中の「挫屈感」は以下の評価をする。
◎：優れている 〇：良い △：普通 ×：大シワ
【００５８】
（１４）ソフト性
表中の「ソフト性」は以下の評価をする。
◎：優れている 〇：良い △：普通 ×：硬い
【００５９】
（１５）腰感
表中の「腰感」は５を普通とし、数が大きくなるほど腰があり、数が小さくなるほど腰がないとして、１から１０の１０段階評価とする。
【００６０】
（１６）折り曲げ回復率
幅１ｃｍ×長さ９ｃｍのテストピースの表面下側し、測定台の端から１ｃｍはみださせて置く、この後はみ出させた部分を上側に折り曲げ９．８Nの荷重を載せ放置する。荷重をかけてからちょうど一時間後に荷重を解放し、解放してからちょうど３０秒後にその折れ目が水平の台からどの程度まで回復しているかを分度器で測定し、水平まで回復した場合（１８０度）を１００％、折れたままで変化がない場合を０％としてその比率で計算し求める。
【００６１】
［実施例１］
島成分であるナイロン−６と海成分である低密度ポリエチレンとを５０／５０で混合紡糸し、繊度９．０ｄｔｅｘの海島型の複合繊維を得た。得られた複合繊維を、カット長５１ｍｍにカットし原綿を得た。これをカードとクロスレイヤーを用いウェブとし、ニードルパンチングを１０００本／ｃｍ2実施し、次いで、１５０℃の熱風チャンバーで加熱処理し、基材が冷える前に３０℃のカレンダーロールでプレスし、目付け４５０ｇ／ｍ2、厚さ１．５ｍｍ、見かけ密度０．３０ｇ／ｃｍ3の不織布を得た。
【００６２】
次に、高分子弾性体クリスボンＴＦ５０Ｐ（１００％伸長応力が１０８０Ｎ／ｃｍ2のポリウレタン樹脂、大日本インキ化学工業（株）製、固形分濃度３０重量％）をジメチルホルムアミドとメチルエチルケトンの混合溶液（混合比４：６）で希釈した含浸溶液（濃度１５％）を、溶液目付け１５０ｇ／ｍ2となるように先に得た不織布の表面に塗布し、基材中に充分しみこませた後、１２０℃の熱風チャンバーで乾燥した。さらに、同じ含浸溶液を目付け１５０ｇ／ｍ2となるように先ほど塗布した面に再度塗布し、基材中に充分しみこませた後、１４０℃の熱風チャンバーで乾燥し、表面側のみポリウレタン樹脂の含浸された含浸基材を得た。このとき含浸付与された高分子弾性体であるポリウレタン樹脂は、充実した状態で表面側より平均１２０μｍの深さまで分布していることを、電顕写真で確認した。基材厚さの８％である。
【００６３】
その後、該含浸基材を８０℃のトルエン中でディップとニップを繰り返してポリエチレン成分を溶解除去し、複合繊維の極細化を行った。その後、９０℃の温水中で基材に含まれているトルエンを共沸除去し、１２０℃の熱風チャンバーで乾燥し、繊維が極細繊維化された皮革様シート状物を得た。
【００６４】
さらに得られた皮革様シート状物の樹脂が含浸付与された面に２００メッシュのグラビアロールで、含浸ポリウレタン樹脂の良溶媒であるジメチルホルムアミドを付与、乾燥し、その表面を粒度＃３２０の研磨ペーパーで研磨し表面繊維を起毛加工して立毛を有するスエード調の皮革様シート状物を得た。
【００６５】
該スエード調皮革様シート状物を含金染料を用いて、染色を行った後、揉み加工をして仕上げた。得られたシート状物の断面を電顕写真で観察したところ高分子弾性体であるポリウレタン樹脂が存在する含浸層は表面側より平均１０５μｍの深さまで分布していることが確認できた。またその含浸層の繊維と高分子弾性体の比率は、２９：７１であり、さらにポリウレタン樹脂の存在しない未含浸部分の繊維目付が２０７ｇ／ｍ2であった。また、含浸層内では極細繊維が繊維束状態で存在し、繊維束内部には高分子弾性体は存在しておらず、極細繊維束を包囲している高分子弾性体の空隙空間では、極細繊維が空間体積の５０％を占めていた。
【００６６】
得られたシート状物はどの方向にも伸びにくく、カンチレバーの値がタテ６．２ｃｍヨコ６．３ｃｍとなり折り曲げ方向の柔らかな素材の特徴がみられた。σ２０／σ５の値はタテ３．７ヨコ４．８と人工皮革として優れた値でありながら、折り曲げ回復率においてその値が５％とほとんど反発力が無い値となった。このような特徴を持ったここで得られた基材は、持った時に高級で柔らかな天然皮革に類似した非常に柔らかで低反発な素材であった。物性を表１に示す。
【００６７】
［実施例２］
実施例１と同じ、ナイロン−６と低密度ポリエチレンとが５０／５０である繊度９．０ｄｔｅｘの海島型の複合繊維を用い、目付けを高くし、ニードルパンチングを１４００本／ｃｍ2に変更した以外は同様にして、目付け５７０ｇ／ｍ2、厚さ２．３ｍｍ、見かけ密度０．２５ｇ／ｃｍ3の不織布を得た。
【００６８】
次に、実施例１と同様の高分子弾性体の含浸溶液（濃度１５％）を、溶液目付け３４０ｇ／ｍ2となるように先に得た不織布の表面に塗布し、基材中に充分しみこませた後、１２０℃の熱風チャンバーで乾燥し、表面側のみポリウレタン樹脂の含浸された含浸基材を得た。このとき含浸付与された高分子弾性体であるポリウレタン樹脂は、充実した形態で表面側より平均１５０μｍの深さまで分布していることを、電顕写真で確認した。基材厚さの６．５％である。
【００６９】
その後、該含浸基材から実施例１と同様にポリエチレン成分を溶解除去し、繊維が極細化された皮革様シート状物を得た。
【００７０】
さらに得られた皮革様シート状物の表面を実施例１と同様に表面処理し、立毛、染色されたスエード調の皮革様シート状物を得た。得られたシート状物の断面を電顕写真で観察したところ高分子弾性体であるポリウレタン樹脂が存在する含浸層は表面側より平均１２８μｍの深さまで分布していることが確認できた。またその含浸層の繊維と高分子弾性体の比率は、２７：７３であり、さらにポリウレタン樹脂の存在しない未含浸部分の繊維目付が２６６ｇ／ｍ2であった。また、含浸層内では極細繊維が繊維束状態で存在し、繊維束内部には高分子弾性体は存在しておらず、極細繊維束を包囲している高分子弾性体の空隙空間では、極細繊維が空間体積の５０％を占めていた。
【００７１】
得られたシート状物はその厚みに比して縦横斜めのどの方向にも伸びにくく、従来の皮革様シート状物では得ることができないレベルのものであった。しかも、カンチレバーの値がタテ６．２ｃｍヨコ６．３ｃｍとなり折り曲げ方向の柔らかな素材の特徴がみられた。また、σ２０／σ５の値がタテ７．０ヨコ８．９と低応力で変形しやすいが、少し伸びると伸びの止まるソフトな天然皮革特有の特徴がみられた。さらに折り曲げ回復率が９％とほとんど反発力が無い値となった。このシート状物は、持った時に高級で柔らかな天然皮革に類似した非常に柔らかで低反発な素材であった。物性を表１に併せて示す。
【００７２】
［実施例３］
実施例１と同じく、ナイロン−６と低密度ポリエチレンとが５０／５０である繊度９．０ｄｔｅｘの海島型の複合繊維を用い、目付けを高くし、ニードルパンチングを１４００本／ｃｍ2に変更した以外は同様にして、目付け８７０ｇ／ｍ2、厚さ２．８ｍｍ、見かけ密度０．３１／ｃｍ3の不織布を得た。
【００７３】
次に、実施例１と同様の高分子弾性体の含浸溶液（濃度１５％）を、溶液目付け３２０ｇ／ｍ2となるように先に得た不織布の表面に塗布し、基材中に充分しみこませた後、１２０℃の熱風チャンバーで乾燥し、ついで同じ含浸溶液を、先ほどと反対の面に、同じく目付け３２０ｇ／ｍ2となるように表面に塗布し、基材中に充分しみこませた後、１２０℃の熱風チャンバーで乾燥し、中心部以外の基材両表面側のみがポリウレタン樹脂を含浸した両面含浸基材を得た。このとき含浸付与された高分子弾性体であるポリウレタン樹脂は、充実した形態で基材両表面側よりそれぞれ平均１５０μｍの深さまで分布していることを、電顕写真で確認した。含浸深さは片面４．５％である。
【００７４】
その後、該含浸基材から実施例１と同様にポリエチレン成分を溶解除去し、繊維が極細化されたシート状物を得た。
【００７５】
その後、シート状物の樹脂が含浸付与された両面を、それぞれ２００メッシュのグラビアロールでジメチルホルムアミドを付与、乾燥し、ついでその両表面を粒度＃３２０の研磨ペーパーで研磨し表面繊維を起毛加工した後、樹脂の未含浸部分である厚みの半分の部位でスライスを行い、スエード調の外観の皮革様シート状物を得た。
【００７６】
さらに得られた皮革様シート状物を実施例１と同様に処理し、染色されたスエード調の皮革様シート状物を得た。得られたシート状物の断面を電顕写真で観察したところ高分子弾性体であるポリウレタン樹脂が存在する含浸層は表面側より平均１２５μｍの深さまで分布していることが確認できた。またその含浸層の繊維と高分子弾性体の比率は、３２：６８であり、さらにポリウレタン樹脂の存在しない未含浸部分の繊維目付が１９５ｇ／ｍ2であった。また、含浸層内では極細繊維が繊維束状態で存在し、繊維束内部には高分子弾性体は存在しておらず、極細繊維束を包囲している高分子弾性体の空隙空間では、極細繊維が空間体積の５０％を占めていた。
【００７７】
得られたシート状物は縦横斜めのどの方向にも伸びにくく、折り曲げ方向の柔らかな素材の特徴がみられた。また、低応力で変形しやすいが、少し伸びると伸びの止まるソフトな天然皮革特有の特徴がみられた。さらに折り曲げ回復率が４％とほとんど反発力が無い値となった。このシート状物は、持った時に高級で柔らかな天然皮革に類似した非常に柔らかで低反発なシート状物であった。物性を表１に併せて示す。
【００７８】
［実施例４］
実施例２と同様の加工を行い繊維が極細化された皮革様シート状物を得た。
【００７９】
さらに得られた皮革様シート状物の表面を立毛化処理する替わりに、銀面調とするために、高分子弾性体層を表面に付与した。
【００８０】
すなわち、高分子弾性体としてＣｕ９４３０ＮＬ（１００％伸長応力が６００Ｎ／ｃｍ2のポリウレタン樹脂、大日精化工業（株）製、固形分濃度３０重量％）をジメチルホルムアミドとメチルエチルケトンの混合溶液（混合比４：６）で希釈したフィルム層用溶液（固形分濃度１５％）を離型紙（ＡＲ―７４Ｍ、厚さ０．２５ｍｍ、旭ロール（株）製）上に目付け１３０ｇ／ｍ2（ｗｅｔ）で塗布し、初めに１００℃で３分間乾燥させた。次にこの得られたフィルム上に、高分子弾性体クリスボンＴＡ２６５（１００％伸長応力が２４５Ｎ／ｃｍ2の架橋型ポリウレタン樹脂、大日本インキ化学工業（株）製、固形分濃度６５重量％）２０部、高分子弾性体クリスボンＴＡ２９０（１００％伸長応力が２４５Ｎ／ｃｍ2の架橋型ポリウレタン樹脂、大日本インキ化学工業（株）製、固形分濃度４５重量％）８０部、コロネートＬ（イソシアネート系架橋剤、日本ポリウレタン（株）製）１５部、クリスボンアクセルＴ（架橋促進剤、大日本インキ化学工業（株）製）３部、ジメチルホルムアミド１０部で配合したバインダー用溶液を、目付け１００ｇ／ｍ2（ｗｅｔ）で塗布し、その上に繊維が極細化処理された該皮革様シート状物の樹脂が含浸付与された面を貼り合わせ面として貼り合わせた後、１００℃で３０秒乾燥し、次いで７０℃で４８時間エージングを行った後、１２時間放置冷却を行い、離型紙を分離し、表面に高分子弾性体の層を持った銀付調の皮革様シート状物を得た。
【００８１】
さらにその後該シート状物の表皮層を有する表面に、１００％伸長応力が３５０Ｎ／ｃｍ2のポリウレタン樹脂を２００メッシュのグラビアロールで仕上げた後、柔軟剤を付与し、揉み加工を行った。
【００８２】
得られた皮革様シート状物の断面を電顕写真で観察したところ高分子弾性体であるポリウレタン樹脂が存在する含浸層は表面側の接着層の下側よりさらに平均１２８μｍの深さまで分布していることが確認できた。またその含浸層の繊維と高分子弾性体の比率は、２７：７３であり、さらにポリウレタン樹脂の存在しない未含浸部分の繊維目付が２６６ｇ／ｍ2であった。また、含浸層内では極細繊維が繊維束状態で存在し、繊維束内部には高分子弾性体は存在しておらず、極細繊維束を包囲している高分子弾性体の空隙空間では、極細繊維が空間体積の５０％を占めていた。
【００８３】
また、この皮革様シート状物は、挫屈感が良好であり、縦横斜めのどの方向にも伸びにくく、折り曲げ方向の柔らかな素材の特徴がみられた。また、低応力で変形しやすいが、少し伸びると伸びの止まるソフトな天然皮革特有の特徴がみられた。さらに折り曲げ回復率が５１％と反発力の低い値となった。このような特徴を持ったここで得られた基材は、持った時に高級で柔らかな天然皮革に類似した非常に柔らかで低反発な素材であった。物性を表１に併せて示す。
【００８４】
［比較例１］
実施例１と同じ、ナイロン−６と低密度ポリエチレンとが５０／５０である繊度８．０ｄｔｅｘの海島型の複合繊維を用い、目付けを高くし、ニードルパンチングを１４００本／ｃｍ2に変更した以外は同様にして、目付け５００ｇ／ｍ2、厚さ１．５ｍｍ、見かけ密度０．３３ｇ／ｃｍ3の不織布を得た。
【００８５】
次に、実施例１で用いた高分子弾性体クリスボンＴＦ５０Ｐ（１００％伸長応力が１０８０Ｎ／ｃｍ2のポリウレタン樹脂、大日本インキ化学工業（株）製）を、実施例１と異なりジメチルホルムアミドのみで溶解した含浸溶液（濃度１５％）を、溶液目付け８７０ｇ／ｍ2となるように含浸させ、１０％ジメチルホルムアミド水溶液中に浸漬して、湿式凝固させた。この後４０℃の温水中で十分洗浄し、高分子弾性体含浸基材を得た。このとき含浸付与された高分子弾性体であるポリウレタン樹脂は、多孔化した形態で全層に分布していることを、電顕写真で確認した。
【００８６】
その後、該含浸基材から実施例１と同様にポリエチレン成分を溶解除去し、繊維が極細化された皮革様シート状物を得た。
【００８７】
さらに得られた皮革様シート状物の表面を実施例１と同様に表面処理し、立毛、染色されたスエード調の皮革様シート状物を得た。得られたシート状物の断面を電顕写真で観察したところ高分子弾性体であるポリウレタン樹脂はシート全層に存在していることが確認できた。またその繊維と高分子弾性体の比率は、６６：３４であり、さらにポリウレタン樹脂の存在しない未含浸部分は存在しなかった。
【００８８】
得られたシート状物は、折り曲げ方向に柔らかく、低応力で変形しやすい特徴がみられたものの、折り曲げ回復率においては７９％と反発の強い素材であり、従来からある柔らかな人工皮革の同じ風合いであった。物性を表１に併せて示す。
【００８９】
［比較例２］
高分子弾性体をよりやわらかくするために、比較例１で用いた含浸溶液の替わりに、高分子弾性体クリスボンＴＦ５０Ｐ（１００％伸長応力が１０８０Ｎ／ｃｍ2のポリウレタン樹脂、大日本インキ化学工業（株）製、固形分濃度３０重量％）と高分子弾性体レザミンＣｕ９４３０ＮＬ（１００％伸長応力が６００Ｎ／ｃｍ2のポリウレタン樹脂、大日精化工業（株）製、固形分濃度３０重量％）を３０：７０となる比率で、ジメチルホルムアミド中に溶解した含浸溶液（濃度１３％）を用い、含浸溶液目付けを７７６ｇ／ｍ2とする以外は比較例１と同様にして繊維が極細化された皮革様シート状物を作成した。
【００９０】
さらに得られた皮革様シート状物の表面を今度は実施例３と同様に両面表面処理し、両面に立毛を有するスエード調の皮革様シート状物を得た。次いで厚みの半分でスライスを行う事によって表面がスエード調の外観の皮革様シート状物を得た。
【００９１】
さらに得られた皮革様シート状物を実施例３と同様に処理し、染色されたスエード調の皮革様シート状物を得た。得られたシート状物の断面を電顕写真で観察したところ高分子弾性体であるポリウレタン樹脂は基材全層に存在していることが確認できた。またその繊維と高分子弾性体の比率は、７１：２９であり、さらにポリウレタン樹脂の存在しない未含浸部分は存在しなかった。またこのシート状物は折り曲げ方向に非常に柔らかいものの、伸び止め性が低いにもかかわらず、折り曲げ回復率が８５％と反発の強い素材であった。物性を表１に併せて示す。
【００９２】
［比較例３］
実施例１と同じ、ナイロン−６と低密度ポリエチレンとが５０／５０である繊度９．０ｄｔｅｘの海島型の複合繊維を用い、目付けを低くした以外は同様にして、目付け３７０ｇ／ｍ2、厚さ１．４ｍｍ、見かけ密度０．２６ｇ／ｃｍ3の不織布を得た。
【００９３】
次いでこの不織布を、高分子弾性体クリスボンＴＦ５０Ｐ／クリスボンＴＦ３００ＴＤ（１００％伸長応力が２７５０Ｎ／ｃｍ2のポリウレタン樹脂、大日本インキ化学工業（株）製、固形分濃度３０重量％）＝６／４のジメチルホルムアミド中に溶解した含浸溶液（固形分濃度１５％）に浸漬・含浸し、含浸液の目付けが９２０ｇ／ｍ2になるよう余分な含浸液をスクイズし、引き続き高分子弾性体クリスボンＴＦ５０Ｐ／クリスボンＴＦ７００Ｓ（１００％伸長応力が３４０Ｎ／ｃｍ2のポリウレタン樹脂、大日本インキ化学工業（株）製、固形分濃度３０重量％）＝９／１のジメチルホルムアミド中に溶解した湿式コート溶液（固形分濃度２０％）を目付７５０ｇ／ｍ2となるように表面にコートした。次いでこの繊維と高分子弾性体とからなるシートを、１２％のジメチルホルムアミド水溶液中に浸漬し湿式凝固させた後、４０℃の温水中で十分洗浄し、１３５℃の熱風チャンバーで乾燥して、海島繊維と高分子弾性体からなる基材上に、高分子弾性体からなる表皮層を持った基材を得た。ここでの高分子弾性体はいずれも湿式凝固により連続多孔を有する多孔質となっており、また含浸付与された高分子弾性体であるポリウレタン樹脂は、多孔化した形態で全層に分布していることを、電顕写真で確認した。
【００９４】
その後、得られた基材から、実施例１と同様にポリエチレン成分を溶解除去し、極細繊維と多孔高分子弾性体からなるシート状物を得た。さらに得られたシート状物の表皮層を有する面にエンボス加工しシボ柄を付与した後、１００％伸長応力が３５０Ｎ／ｃｍ2のポリウレタン樹脂を２００メッシュのグラビアロールで仕上げ塗布した後、柔軟剤を付与し、揉み加工を行った。
【００９５】
得られた銀面を有するシート状物は、そのシート状物の断面を電顕写真で観察したところ高分子弾性体であるポリウレタン樹脂は断面全層に存在していることが確認できた。またその繊維と高分子弾性体の比率は、３９：６１であり、さらにポリウレタン樹脂の存在しない未含浸部分は存在しなかった。また、このシート状物は、折り曲げ方向にしっかり感のある硬めの素材で腰はあるものの、ソフト性に欠け、折り曲げ回復率が８３％と反発の強い素材であり、また、表面の銀面層における挫屈感もあまり良くないものであった。また、その表面には含浸層の極細繊維に由来する毛羽が発生し、表面品位も低いものであった。物性を表１に併せて示す。
【００９６】
［比較例４］
海島繊維からなる目付け３７０ｇ／ｍ2、厚さ１．４ｍｍ、見かけ密度０．２６ｇ／ｃｍ3の不織布を、比較例３と同様の方法で作成した。
【００９７】
次に、比較例１で用いたものと同様の含浸溶液（固形分濃度１５％）を用いて、含浸溶液目付けを９２０ｇ／ｍ2とする以外は比較例１と同様に含浸、抽出処理して繊維が極細化された皮革様シート状物を作成した。
【００９８】
一方、実施例４と同様にして、銀面調とするための高分子弾性体層を、ラミネート法にて表面に付与し、さらに実施例４と同様に、表皮層を有する表面に、ポリウレタン樹脂を２００メッシュのグラビアロールで仕上げた後、柔軟剤を付与し、揉み加工を行った。
【００９９】
得られた銀付き調シート状物は、その断面を電顕写真で観察したところ高分子弾性体であるポリウレタン樹脂は基材全層に存在していることが確認できた。またその繊維と高分子弾性体の比率は、５１：４９であり、さらにポリウレタン樹脂の存在しない未含浸部分は存在しなかった。またこのシート状物は、折り曲げ方向にしっかり感のある硬めの素材であり、腰はあるもののソフト性に欠け、折り曲げ回復率が８３％と反発の強い素材であり、また、表面の銀面層における挫屈感は良好であるものの、表面の突っ張り感があり堅い物となった。物性を表１に併せて示す。
【０１００】
【表１】
［比較例５］
実施例１と同様の目付け４５０ｇ／ｍ2、厚さ１．５ｍｍ、見かけ密度０．３０ｇ／ｃｍ3の不織布の表面から、同じく実施例１で用いた高分子弾性体の含浸溶液（濃度１５％）を、基材の裏側まで充分しみこむまで何度も塗布を繰り返し十分にしみこませた後、１４０℃の熱風チャンバーで乾燥し、基材の全層にポリウレタン樹脂の含浸された基材を得た。このとき含浸付与された高分子弾性体であるポリウレタン樹脂は、充実した形態で基材全層にわたって分布している事を、電顕写真で確認した。
【０１０２】
その後、該基材から、実施例１と同様にポリエチレン成分を溶解除去し、繊維が極細化されたシート状物を得た。得られたシート状物は非常にボリューム感のある反発の高いベースとなり本発明の目的であるソフトで低反発な素材とは異なるものとなった。
【０１０３】
【発明の効果】
本発明によれば、従来の皮革様シート状物では持ち得なかった伸び止め感が強いにもかかわらず、ソフトでかつ低反発である天然皮革の物性に類似した人工の皮革様シート状物およびその製造方法を提供することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a leather-like sheet and a method for producing the same. More particularly, the present invention relates to an artificial leather-like sheet which is soft and has low resilience, which is similar to the physical properties of natural leather, despite having a strong anti-stretch feeling, and a method for producing the same.
[0002]
[Prior art]
As an alternative to natural leather, a so-called artificial leather-like sheet using a fiber and a polymer elastic material has been widely used. However, although artificial leather has relatively superior physical properties compared to natural leather, it has not yet reached the level of high-quality natural leather in terms of appearance and feeling. As for the appearance, various finishing methods and the like have been studied in order to solve the problem, and a number of appearances similar to natural leather and further appearances that could not be expressed with natural leather have been proposed. However, although various studies have been made on the texture, very soft materials have been proposed, but very soft materials with low rebound and dampness, which are the characteristics of excellent natural leather, are still available. Absent.
[0003]
For example, in Japanese Patent No. 3155135, a web is formed from ultrafine composite fibers composed of at least two kinds of high molecular polymers, and needle punching is performed in the thickness direction of the web to form an entangled fibrous base material. A method is disclosed in which the entangled fibrous base material is impregnated with a polymer elastic material and solidified, and thereafter, the conjugate fibers constituting the entangled fibrous base material are ultrafine. However, although the leather-like sheet obtained by such a method is soft, the leather-like sheet has a resilience-like rubber-like texture due to the characteristics of the impregnated polymer elastic body, and is an excellent texture of natural leather. However, a sheet having a very soft texture with a low rebound and a damp feeling could not be realized.
[0004]
[Patent Document 1]
Japanese Patent No. 3155135
[0005]
[Problems to be solved by the invention]
An object of the present invention is to provide an artificial leather-like sheet material similar to the physical properties of natural leather, which is soft and has low resilience, despite having a strong stretch-stopping feeling which cannot be obtained with these conventional leather-like sheet materials. And a method for producing the same.
[0006]
[Means for Solving the Problems]
The leather-like sheet material of the present invention is a sheet material comprising microfibers and a polymer elastic material, wherein the polymer elastic material is present from one surface to a depth of 25 μm or more; There is an unimpregnated layer in which no fine fibers are present, and in the impregnated layer, the ultrafine fibers are present in a fiber bundle state, and the polymer elastic body surrounds the outer periphery of the fiber bundle. Is not present. Further, the thickness of the impregnated layer is 25 to 300 μm, and the basis weight of the unimpregnated layer portion is 30 to 500 g / m Two It is preferable that the polymer elastic body of the impregnated layer is a solid type or an independent porous type, and the bending recovery rate is 75% or less.
[0007]
Further, the first of the method for producing a leather-like sheet material of the present invention is that an impregnated layer and an unimpregnated layer are formed on a sheet made of sea-island fibers having an ultrafine fiber forming property of two or more components having different solvent solubilities. The method is characterized in that a polymer elastic solution is applied and solidified from one surface so as to generate, and then the sea component of the sea-island fiber is removed using a solvent that dissolves the sea component of the sea-island fiber.
[0008]
The second method of the present invention for producing a leather-like sheet-like material comprises, on a sheet made of ultrafine fiber-forming sea-island fibers composed of two or more components having different solvent solubilities, a center portion. A polymer elastic solution is applied from both surfaces and solidified to form an impregnated layer so that an unimpregnated layer is generated, and then the sea component of the sea-island fiber is removed using a solvent that dissolves the sea component of the sea-island fiber. The non-impregnated layer portion is sliced and divided into two parts.
[0009]
Furthermore, in the production method of the present invention, before the application of the polymer elastic solution, the surface of the sheet made of sea-island fibers is pressed in advance at a temperature higher than the softening temperature of the sea component constituting the sea-island fiber and lower than the softening temperature of the island component. In addition, it is preferable that the method of solidifying the polymer elastic solution be a dry method.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
TECHNICAL FIELD The present invention relates to a sheet-like material composed of ultrafine fibers and a polymer elastic material, which is a leather-like sheet material having an impregnated layer in which the polymer elastic material is present and an unimpregnated layer in which the polymer elastic material is not present.
[0011]
The ultrafine fiber in the present invention is an ultrafine fiber having a fineness of 0.2 dtex or less, preferably 0.1 dtex or less, particularly preferably 0.0001 to 0.05 dtex. Examples of such ultrafine fibers include polyester fibers such as polyethylene terephthalate and polybutylene terephthalate, and polyamide fibers such as nylon 6, nylon 66, and nylon 12. Further, in the present invention, it is necessary that there exist ultrafine converging fibers in which the ultrafine fibers are aggregated as a bundle. For example, as such an ultrafine bundled fiber, at least one component of a multicomponent fiber obtained by spinning as a sea-island type fiber from a polymer composition of two or more components having different solvent solubilities by a composite spinning method, a mixed spinning method or the like. Fibers which have been removed and made finer are exemplified. However, when the ultrafine fibers are in a bundle form, one bundle preferably contains 10 to 5000, more preferably 100 to 2,000, ultrafine fibers.
[0012]
The sheet-like material of the present invention is composed of microfibers and a polymer elastic body. However, there is no particular limitation as long as the above-mentioned sheet-like material is mainly composed of microfibers. The part may contain ultrafine fibers. Such a substrate may be a woven or knitted fabric, but in order to improve the feeling, a nonwoven fabric is mainly used, and it is preferable that the woven or knitted fabric is partially included or not included at all for reinforcement.
[0013]
Furthermore, examples of the polymer elastic body used in the leather-like sheet of the present invention include polyurethane resin elastomer, polyurea elastomer, polyurethane resin / polyurea elastomer, polyacrylic resin, acrylonitrile / butadiene elastomer, styrene / butadiene elastomer, and the like. Among them, polyurethane resin-based polymers such as polyurethane resin elastomer, polyurea elastomer, and polyurethane resin / polyurea elastomer are preferable.
[0014]
The 100% elongation modulus of the elastic polymer present in the impregnated layer is 200 to 5000 N / cm. Two And more preferably 300 to 4000 N / cm. Two And particularly preferably, 400 to 3000 N / cm. Two It is. 100% elongation modulus is 200 N / cm Two If it is less than 1, the obtained substrate is rich in flexibility, but heat resistance, solvent resistance and the like tend to decrease. Conversely, 5000 N / cm Two When the ratio exceeds, the texture of the obtained substrate tends to be hard. As a method for adjusting the 100% elongation modulus of the elastic polymer to a preferable range, for example, when a polyurethane resin elastomer is used, it can be easily performed by adjusting the content of the organic diisocyanate and the amount of the chain extender in the polymer. .
[0015]
The polymer elastic body of the impregnated layer is preferably of a solid type or an independent porous type. In the case of a continuous porous material obtained by a wet coagulation method or the like, the obtained leather-like sheet tends to have a reduced elongation-preventing effect.
[0016]
The leather-like sheet material of the present invention has both an impregnated layer in which the polymer elastic body is present from one surface to a depth of 25 μm or more, and an unimpregnated layer in which the polymer elastic body is not present, Further, the thickness of the impregnated layer is preferably from 25 to 300 μm, more preferably from 50 to 250 μm, most preferably from 75 to 200 μm. At this time, if the layer in which the elastic polymer is present becomes thinner, the strength of the obtained sheet-like material becomes weaker, and the stretchability during processing also decreases, and the sheet tends to elongate in the longitudinal direction. On the other hand, when the layer is thick, the texture becomes strong and firm, but tends to be stiff. In particular, when the polymer elastic body of the impregnated layer, which has excellent stretch resistance, is a solid type or an independent porous type, it tends to be stiffer than when a continuous porous polymer elastic body is used. Need to be thinner.
[0017]
Further, the ratio of the fiber and the elastic polymer in the impregnated layer is preferably in the range of 5:95 to 95: 5, more preferably 10:90 to 50:50, and particularly preferably 15:85 to 40. : 60 is preferable. At this time, if the ratio of the elastic polymer is small, the strength of the obtained sheet-like material tends to be weak. On the other hand, when the ratio of the polymer elastic body in the impregnated layer is large, the texture of the obtained sheet-like material becomes hard. In particular, when the polymer elastic body is a solid type, it tends to be a sheet having strong resilience due to its characteristics.
[0018]
The leather-like sheet material of the present invention needs to have an unimpregnated layer that is free of the elastic polymer composed of only fibers. In the present invention, the presence of the non-impregnated portion provides a gradient in the distribution of stress on the front and back surfaces, and provides a well-balanced, low-repulsion, and very good texture. Furthermore, the fiber basis weight of the unimpregnated part is 30 to 500 g / m. Two And more preferably in the range of 40 to 400 g / m Two And in particular, 50 to 300 g / m Two Is preferably within the range. When the basis weight of the non-impregnated part is low, the properties become almost the same as those of a conventional leather-like sheet having no non-impregnated part, and it tends to be difficult to achieve both elongation resistance and softness. On the other hand, if the unimpregnated portion is too large, the difference from the non-impregnated nonwoven fabric tends to be small, and the elongation resistance tends to decrease.
[0019]
The leather-like sheet material of the present invention comprises the above-mentioned impregnated layer and unimpregnated layer, but the most characteristic point of the present invention is that in the impregnated layer, ultrafine fibers exist in a fiber bundle state. That is, the polymer elastic body constituting the impregnated layer surrounds the outer periphery of the fiber bundle, but the polymer elastic body does not exist inside the fiber bundle.
[0020]
Unlike the present invention, when the ultrafine fibers have penetrated into the impregnated layer in the form of ultrafine single fibers instead of fiber bundles, the ultrafine fibers are densely present between the polymer elastic bodies, and The reinforced polymer elastic body tends to be hard and difficult to deform. Also, even if the fiber and the polymer elastic material are debonded by any means, if the fiber is infiltrated in the state of ultrafine single fiber, the distance between the microfine fiber and the polymer elastic material is short and the degree of freedom of the fiber is small. And tends to form a layer that is necessarily a rigid structure. In contrast, when the microfibers are present in a fiber bundle, the interfiber voids are larger than the entire fiber basis weight due to the higher fiber density in the fiber bundle, and the polymer elastic body is present in a large mass. However, the properties of the elastic body are strongly brought out, and the elastic body is easily deformed. Further, in the present invention, the polymer elastic body surrounds the fiber bundle, and since the polymer elastic body does not exist inside the fiber bundle, the distance between the microfine fiber and the polymer elastic body is large, and the degree of freedom of the fiber is large. It becomes a flexible structure and can realize a flexible feeling.
[0021]
In the present invention, since the polymer elastic body surrounds the fiber bundle, only the polymer elastic body is deformed at the time of small deformation of the sheet-like material and only a small stress is generated. Deformation is transmitted to the substrate and a large stress is generated. In order for such a phenomenon to occur, it is necessary that the fiber bundle is sufficiently surrounded by the elastic polymer, and if possible, the cross section is preferably substantially circular. For example, if there is a crack in the polymer elastic body around the fiber bundle, or if there is a part or direction in which the stress to the fiber bundle is difficult to transmit in the space around the fiber bundle, only when the sheet-like material is greatly deformed However, it is not preferable because the composite effect of the fiber and the polymer elastic body does not occur.
[0022]
Further, it is preferable that the ultrafine fibers occupy 20 to 80% by volume, more preferably 30 to 70%, most preferably 40 to 60%, of the void space of the polymer elastic body surrounding the fiber bundle. The occupied state is preferred. If the void space around the fiber bundle is too large, the stress to the fiber bundle is difficult to be transmitted, and the feeling of retaining the stretch tends to be low. Conversely, if the void space is too small, it tends to be hard. In order for the polymer elastic body to have such a structure, it is preferable that the impregnated layer composed of the microfine fibers and the polymer elastic body is a solid layer or has an independent porous structure in which voids are not continuous. .
[0023]
The leather-like sheet of the present invention is very soft and low resilience due to its structure. Here, the bending recovery ratio, which is a substitute characteristic of the low resilience, is preferably 75% or less, more preferably 60% or less, and most preferably 55% or less. The bending recovery rate is as follows. A sample with a width of 1 cm is placed with the impregnated layer on the lower side, the edge of 1 cm is bent at 180 °, and left for 1 hour under a load of 9.8 N, and after 30 seconds from the removal of the load, the recovery is obtained. The rate is shown assuming that 180 ° is 100%, and 0% is in the case of a broken state. The smaller the value of the fold-recovery ratio is, the more damp soft it is without rebound.
[0024]
It is also preferable that the leather-like sheet material of the present invention has a suede-like or nubuck-like surface having a silvery tone or raised hair. Here, the leather-like sheet-like material having a silver tone is a leather-like sheet having naps in which the impregnated layer is unevenly distributed on one side of the sheet-like material and the surface of the unevenly distributed side is silver-toned. The sheet-like material is one in which the impregnated layer is unevenly distributed on one side of the sheet-like material, and the outermost surface on the unevenly distributed side has the fine fiber nap.
[0025]
Such a leather-like sheet material of the present invention can be obtained by another method for producing a leather-like sheet material of the present invention. That is, a polymer elastic solution is applied from one surface to a sheet made of sea-island fibers having an ultrafine fiber forming property composed of two or more components having different solvent solubilities so that an impregnated layer and an unimpregnated layer are generated. A method of coagulating and then removing the sea component of the fiber using a solvent that dissolves the sea component of the sea-island fiber, or on a sheet made of ultra-fine fiber-forming sea-island fiber composed of two or more components having different solvent solubilities Then, a polymer elastic solution is applied from both surfaces and solidified to form an impregnated layer so that an unimpregnated layer is generated at the center, and then the sea component of the fiber is dissolved using a solvent that dissolves the sea component of the sea-island fiber. This is a method of removing, then slicing at an unimpregnated layer portion and dividing into two.
[0026]
By doing so, the ultrafine fibers constituting the impregnated layer exist in a fiber bundle state, and the polymer elastic body constituting the impregnated layer surrounds the fiber bundle, but the polymer elastic body is contained inside the fiber bundle. A soft, low-resilience leather-like sheet having no body can be produced.
[0027]
Examples of the ultrafine fiber-forming islands-in-sea fiber comprising two or more components having different solvent solubilities of the present invention include, for example, a composite spinning method, a blending method, and a polymer composition comprising two or more components having different solvent solubilities. It is spun by a spinning method or the like to obtain sea-island type fibers. At this time, the fineness of the island component does not need to be particularly defined, but is preferably 0.2 dtex or less, more preferably 0.1 dtex or less, and particularly preferably 0.0001 to 0.05 dtex. .
[0028]
Further, as a preferred combination of two or more polymer compositions having different solvent solubility, when polyester such as polyethylene terephthalate or polybutylene terephthalate is selected as the insoluble component, polyethylene, polypropylene, or polystyrene is used as the easily soluble component. When polyamides such as nylon 6, nylon 66, and nylon 12 are selected as insoluble components, polyesters and polyolefins are preferably selected as easily soluble components.
[0029]
The sheet made of such ultrafine fiber-forming sea-island fibers used in the present invention is not particularly limited as long as it is a sheet, and may be any of various woven or knitted fabrics or nonwoven fabrics. Preferably, it is a base. For example, in order to convert the fibers into a nonwoven fabric, a known card, layer, needle locker, fluid entanglement device, or the like can be used, and a dense three-dimensionally woven nonwoven fabric having a high entangled fiber density can be obtained.
[0030]
Further, before the entangled fibrous sheet obtained here is applied with the polymer elastic solution, the softening temperature of the sea component constituting the sea-island fiber is equal to or higher than the softening temperature of the island component, and the sheet is formed of the sea-island fiber in advance. It is preferable to adjust the thickness and the surface by pressing the surface. Here, by adjusting the thickness, the thickness of the finally obtained product can be controlled. Further, by adjusting the surface, it is possible to control the smoothness of the product surface. By adjusting the heating and pressurizing conditions, the degree of penetration of the polymer elastic solution is adjusted. When the prepared surface forms a film by fusing, etc., the applied polymer elastic material is hardly penetrated, while on the other hand, when the film cannot be formed by fusing, etc., and the fiber density of the outermost surface is low, the polymer The elastic solution is well penetrated.
[0031]
In the present invention, in a range of 25 to 300 μm from one of the prepared surfaces of the base material containing the ultrafine fiber-forming sea-island fibers obtained in this manner, a polymer elastic body that surrounds the sea-island fibers without voids is provided. It is necessary to form an impregnated layer containing. For example, the thickness of the impregnated layer is adjusted by adjusting the degree of penetration of the polymer elastic solution into the base material.
[0032]
In addition, in the polymer elastic body given here, it is OK that closed cells such as air bubbles partially exist around the fiber, but basically there is no void between the sea-island fiber and the polymer elastic body. Is preferred. If there is a gap, the elastic polymer cannot eventually surround the outer periphery of the ultrafine fiber bundle. Further, it is preferable that there is no gap between the fiber and the polymer elastic body, and that no adhesion occurs.
[0033]
In order to form such an impregnated layer, the method of solidifying the polymer elastic solution is preferably a dry method, for example, an organic solvent solution or dispersion of the polymer elastic material from one surface of the fibrous base material. (Including an aqueous emulsion) is preferably applied, and is sufficiently impregnated into the substrate, and then solidified by heating and drying. Furthermore, in order to adjust the impregnation depth, the number of times of application is not one, but a plurality of times, for example, application and drying are repeated in 2 to 5 times, so that the amount of impregnation of the polymer elastic body closer to the surface layer is repeated. Can be increased, and the texture can be improved.
[0034]
At this time, the solid component concentration of the polymer elastic body liquid to be applied is preferably 5 to 50%. Further, the content is more preferably 7 to 30%, and most preferably 10 to 20%. If the concentration is less than 5%, the viscosity of the polymer elastic solution is too low, so that it is difficult to process, such as too much penetrating into the base material, or flowing over the surface of the base material to make it difficult to uniformly penetrate. Even if it can be applied successfully, the impregnated layer is often 25 μm or less from one surface of the substrate. On the other hand, the higher the concentration, the higher the viscosity of the polymer elastic body solution tends to be, the balance of the degree of penetration into the substrate tends to be lost, and it tends to be difficult to uniformly apply the polymer elastic body. In particular, if the solid component concentration is too high, the amount of the elastic polymer to be applied is too large, and it tends to be a stiff texture with a repulsive feeling, which is different from the soft and low resilience material targeted by the present invention. Tend to be.
[0035]
Further, the degree of permeation into the substrate can be adjusted by the viscosity of the elastic polymer solution and the surface tension applied here. The viscosity of the polymer elastic body can be adjusted by using a general thickener in addition to adjusting its concentration. In addition, the surface tension of the polymer elastic solution can be controlled by using various additives in the solution.
[0036]
Further, in the present invention, it is preferable that the surface on the side where the impregnated layer is unevenly distributed has an appearance suitable as leather, and any known method can be used for forming the skin layer.
[0037]
In the production method of the present invention, the sea component is then removed using a solvent that dissolves the sea component of the sea-island fiber. It is necessary that this solvent does not dissolve the island component of the ultrafine fibers. The solvent may dissolve the elastic polymer used in the impregnated layer in a small amount, but preferably does not dissolve it. By removing the sea component of the sea-island type fiber in this manner, a structure is formed in the impregnated layer in which the polymer elastic body is not bonded to the ultrafine fiber of the island component. More specifically, for example, when nylon is used for the island component and polyethylene is used for the sea component, it is preferable to use toluene. It is also a preferred method to use a heated solvent to increase the extraction efficiency.
[0038]
Further, in the production method of the present invention, the base material containing the ultrafine fiber-forming sea-island fibers composed of two or more components having different solvent solubilities comprises the polymer elastic body that surrounds the sea-island fibers without voids. A method of forming an impregnated layer in a range of 25 to 300 μm from both surfaces of the base material, then removing the sea component using a solvent that dissolves the sea component of the sea-island fiber, and then slicing at a central portion of the thickness. is suggesting.
[0039]
By doing so, high productivity can be obtained, and stable high workability can be obtained in the processing of thin fabric. In the method of using only one side in the production of the thin material of the present invention, wrinkles are generated from the softness of the base material in the step of removing the sea component using a solvent that dissolves the sea component of the sea-island fiber, There was a tendency for problems in workability, such as elongation due to tension, to occur. Those with resin applied on both sides are firm and the processing is stable and very easy. Further, in the double-sided impregnation, since there is no unimpregnated portion in contact with the roll surface during the process, the generation of fluff and the like due to the impregnated portion is small, and the process stability tends to be high.
[0040]
One of the obtained leather-like sheet-like objects having a raised type appearance is further brushed by subjecting the surface where the impregnated layer is present to a gravure treatment or buffing a polymer elastic material. And dyeing, softening agent imparting, and kneading can be performed as necessary.
[0041]
On the other hand, the obtained leather-like sheet-like material having a grain type appearance is another example of a surface of a polymer elastic body having a suitable appearance as a leather on the surface where the impregnated layer is present. It can be created by adding layers. As the method of forming the skin layer, any known method can be used.For example, a solution or dispersion liquid composed of a polymer elastic material is laminated or coated on a base material to form a skin layer with a silver tone. can do. Further, it is also preferable that the outermost surface is further prepared by subjecting the thus obtained silver-coated surface to a gravure treatment or an emboss treatment with a polymer elastic material as necessary.
[0042]
Further, in the production method of the present invention, it is also preferable that the base material thus obtained is subjected to kneading. As a method of the kneading process, for example, a method in which a sheet-like material is gripped by a clamp and one of the clamps is driven so that kneading deformation is applied to the sheet, or a sheet-like material is placed between a stay having two combined projections. There is a method of rubbing while pushing the projections through the through sheet.
[0043]
The leather-like sheet of the present invention obtained in this manner is an extremely leathery sheet which has the strength of anti-stretching and the low-rebound resilience characteristic of natural leather, which cannot be possessed by conventional leather-like sheets. It has a soft texture.
[0044]
【Example】
Hereinafter, the present invention will be further described with reference to Examples, but the present invention is not limited thereto. Unless otherwise specified in the examples, percentages (%) and ratios indicate% by weight or percentage by weight. The measured values in the examples are based on the following methods.
[0045]
(1) 100% elongation stress
A test piece taken from the resin film (thickness: about 0.1 mm) was subjected to an elongation test at 100% / min with a constant-speed elongation tester, and the load at the time of 100% elongation was read to be N / cm. Two Convert to unit. The test piece complies with the JIS-K-6301-2 type dumbbell method.
[0046]
(2) Depth of impregnated layer
It is measured from a cross-sectional electron micrograph of the substrate, and the average value is adopted.
[0047]
(3) Thickness
Spring type dial gauge (load 1.18N / cm Two ).
[0048]
(4) Weight
A test piece cut into a size of 10 cm × 10 cm is measured with a precision balance.
[0049]
(5) σ5 / σ20 / tensile strength / elongation
A test piece collected from the leather-like sheet was subjected to an elongation test using a constant-speed elongation tester, and the results were shown as values of the load at 5%, 20% elongation, and at break. The elongation at break is also measured. The test piece complies with JIS-K-6550 5-2-1.
[0050]
(6) Tearing
A cut is made in a test piece collected from a leather-like sheet material, and an elongation test is performed using a constant-speed elongation tester. A change in load at the time of tear is shown as an average value.
[0051]
(7) Peel strength
A PVC sheet obtained by bonding a plain woven cloth of the same size to the silver layer side of a test piece having a width of 2.5 cm and a length of 15 cm is bonded with a urethane adhesive. The test piece is marked with 5 sections at intervals of 2 cm, and a peel test is performed at a speed of 50 mm / min using a constant-speed tensile tester. The peeling strength at this time is recorded on a recorder, the minimum value of each part in 5 sections at 2 cm intervals is read, and the average value of the 5 points is converted and displayed per 1 cm width.
[0052]
(8) Wear
The weight change (mg) at the time of abrasion 100 times is measured by a Taber abrasion tester under a load of 9.8N with a load of # 280.
[0053]
(9) Weight of unimpregnated layer
Subtract the impregnated layer depth b of (2) from the total thickness a of the impregnated base material before extraction, divide the value by the total thickness a, calculate the ratio of the unimpregnated layer portion, and extract the ratio. The weight is calculated by multiplying by the following fiber weight (weight before extraction × constituent ratio of unextracted fibers) c.
(Basis weight of unimpregnated layer portion) = ((ab) / a) × c
[0054]
(10) Fiber weight of impregnated layer
By dividing the impregnated layer depth b of (2) by the total thickness a of the impregnated base material before extraction, the ratio of the impregnated layer portion was calculated, and the fiber basis weight after extraction (basis weight before extraction x unapplied) was calculated. The weight per unit area of the impregnated layer is calculated by multiplying the extracted fiber composition ratio c).
(Fiber weight of impregnated layer portion) = (b / a) × c
[0055]
(11) Weight of elastic polymer at impregnation layer
Next, the density of the impregnating solution of the elastic polymer is multiplied by the weight of the applied solution to calculate the elastic polymer weight of the impregnated layer portion.
[0056]
(12) Appearance
"Appearance" in the table is evaluated as follows.
◎: Excellent 〇: Good △: Normal ×: Poor
[0057]
(13) Feeling stiff
The "buckling feeling" in the table is evaluated as follows.
◎: Excellent 〇: Good △: Normal ×: Great wrinkle
[0058]
(14) Softness
"Softness" in the table is evaluated as follows.
◎: Excellent 〇: Good △: Normal ×: Hard
[0059]
(15) Feeling of waist
The “waist feeling” in the table is assumed to be 5 as usual, and the larger the number, the more the waist, and the smaller the number, the less the waist.
[0060]
(16) Bending recovery rate
The test piece having a width of 1 cm and a length of 9 cm is placed below the surface of the test piece and protruded from the end of the measuring table by 1 cm. Then, the protruding portion is bent upward and a load of 9.8 N is placed thereon. Just one hour after applying the load, the load is released, and exactly 30 seconds after the release, the degree of the fold being recovered from the horizontal platform is measured with a protractor. Degree) is set to 100%, and the case where there is no change due to being broken is set to 0%, and the ratio is calculated and calculated.
[0061]
[Example 1]
Nylon-6 as an island component and low-density polyethylene as a sea component were mixed and spun at 50/50 to obtain a sea-island composite fiber having a fineness of 9.0 dtex. The obtained composite fiber was cut into a cut length of 51 mm to obtain a raw cotton. This is made into a web using a card and a cross layer, and needle punching is performed at 1000 pieces / cm. Two And then heat-treated in a hot air chamber at 150 ° C. and pressed with a calender roll at 30 ° C. before the substrate cooled, and a basis weight of 450 g / m 2. Two , Thickness 1.5mm, apparent density 0.30g / cm Three Was obtained.
[0062]
Next, a polymer elastic material Chris Bon TF50P (100% elongation stress is 1080 N / cm Two Of a polyurethane resin (manufactured by Dainippon Ink and Chemicals, Inc., solid content concentration 30% by weight) with a mixed solution of dimethylformamide and methyl ethyl ketone (mixing ratio 4: 6) (concentration 15%). 150g / m Two Was applied to the surface of the previously obtained nonwoven fabric, soaked into the substrate, and dried in a hot air chamber at 120 ° C. Further, the same impregnating solution is weighed 150 g / m. Two Was applied again to the previously applied surface so as to be sufficiently impregnated into the substrate, and then dried in a hot air chamber at 140 ° C. to obtain an impregnated substrate impregnated with a polyurethane resin only on the surface side. At this time, it was confirmed by an electron micrograph that the impregnated polyurethane resin as a polymer elastic body was distributed in a solid state to an average depth of 120 μm from the surface side. 8% of the substrate thickness.
[0063]
Thereafter, the impregnated substrate was repeatedly dipped and nipped in toluene at 80 ° C. to dissolve and remove the polyethylene component, thereby making the composite fiber extremely fine. Thereafter, toluene contained in the substrate was azeotropically removed in hot water at 90 ° C., and dried in a hot-air chamber at 120 ° C. to obtain a leather-like sheet material in which fibers were converted to ultrafine fibers.
[0064]
Further, dimethylformamide, which is a good solvent for the impregnated polyurethane resin, is applied to the surface of the obtained leather-like sheet-like material to which the resin is impregnated by a gravure roll of 200 mesh and dried, and the surface is polished paper having a particle size of # 320. Then, the surface fibers were raised to obtain a suede-like leather-like sheet having nap.
[0065]
The suede-like leather-like sheet was dyed using a gold-containing dye, and then rubbed to finish. Observation of the cross section of the obtained sheet-like material by an electron micrograph confirmed that the impregnated layer in which the polyurethane resin as the polymer elastic body was present was distributed from the surface side to an average depth of 105 μm. The ratio of the fibers in the impregnated layer to the elastic polymer was 29:71, and the fiber weight of the unimpregnated portion where no polyurethane resin was present was 207 g / m 2. Two Met. In the impregnated layer, the ultrafine fibers exist in a fiber bundle state, and the polymer elastic body does not exist inside the fiber bundle, and in the void space of the polymer elastic body surrounding the microfine fiber bundle, The fibers occupied 50% of the space volume.
[0066]
The obtained sheet-like material was hardly stretched in any direction, and the value of the cantilever was 6.2 cm in length and 6.3 cm in width, indicating a characteristic of a soft material in the bending direction. The value of σ20 / σ5 was a value of almost 3.7% in width and 4.8, which is an excellent value as an artificial leather, but the value of the bending recovery rate was 5%, and there was almost no repulsion. The substrate thus obtained, having such characteristics, was a very soft and low resilience material similar to high-grade soft natural leather when held. Table 1 shows the physical properties.
[0067]
[Example 2]
As in Example 1, sea-island composite fibers having a fineness of 9.0 dtex in which nylon-6 and low-density polyethylene are 50/50 are used, the basis weight is increased, and needle punching is performed at 1,400 needles / cm. Two 570 g / m2, except that the weight was changed to Two 2.3mm thick, apparent density 0.25g / cm Three Was obtained.
[0068]
Next, the same impregnation solution (concentration: 15%) of the polymer elastic material as in Example 1 was applied to a solution weight of 340 g / m 2. Two Was applied to the surface of the previously obtained nonwoven fabric, soaked in the substrate, and dried in a hot air chamber at 120 ° C. to obtain an impregnated substrate impregnated with a polyurethane resin only on the surface side. At this time, it was confirmed by electron micrographs that the impregnated polyurethane resin as a polymer elastic body was distributed in a solid form to an average depth of 150 μm from the surface side. 6.5% of the substrate thickness.
[0069]
Thereafter, the polyethylene component was dissolved and removed from the impregnated substrate in the same manner as in Example 1 to obtain a leather-like sheet having extremely fine fibers.
[0070]
Further, the surface of the obtained leather-like sheet was subjected to a surface treatment in the same manner as in Example 1 to obtain a napped and dyed suede-like leather-like sheet. Observation of the cross section of the obtained sheet-like material by an electron micrograph confirmed that the impregnated layer in which the polyurethane resin as a polymer elastic body was present was distributed from the surface side to an average depth of 128 μm. The ratio of the fibers in the impregnated layer to the elastic polymer was 27:73, and the fiber weight of the non-impregnated portion where no polyurethane resin was present was 266 g / m 2. Two Met. In the impregnated layer, the ultrafine fibers exist in a fiber bundle state, and the polymer elastic body does not exist inside the fiber bundle, and in the void space of the polymer elastic body surrounding the microfine fiber bundle, The fibers occupied 50% of the space volume.
[0071]
The obtained sheet-like material was hardly stretched in any of the vertical, horizontal and oblique directions compared to its thickness, and was at a level that could not be obtained with a conventional leather-like sheet-like material. Moreover, the value of the cantilever was 6.2 cm in width and 6.3 cm in width, and the characteristic of the material in the bending direction was soft. In addition, although the value of σ20 / σ5 was as low as 7.0 horizontal 8.9 and easily deformed due to low stress, the characteristic characteristic of soft natural leather, which stops elongating a little, was observed. Further, the bending recovery rate was 9%, which was a value with almost no repulsive force. The sheet was a very soft, low resilience material similar to high-grade soft natural leather when held. Physical properties are also shown in Table 1.
[0072]
[Example 3]
As in Example 1, sea-island composite fibers having a fineness of 9.0 dtex in which nylon-6 and low-density polyethylene were 50/50 were used, the basis weight was increased, and needle punching was performed at 1,400 needles / cm. Two 870 g / m2 except that the weight was changed to Two , Thickness 2.8mm, apparent density 0.31 / cm Three Was obtained.
[0073]
Next, the same impregnating solution (concentration: 15%) of the polymer elastic material as in Example 1 was applied to a solution weight of 320 g / m 2. Two Is applied to the surface of the previously obtained non-woven fabric, soaked in the base material, dried in a hot air chamber at 120 ° C., and then the same impregnating solution was applied on the opposite surface to the same weight as above, 320 g in weight. / M Two It is applied to the surface so that it becomes soaked, and is sufficiently impregnated into the base material, and then dried in a 120 ° C. hot air chamber to obtain a double-sided impregnated base material in which only the base surface except the center is impregnated with the polyurethane resin. Was. At this time, it was confirmed by an electron micrograph that the polyurethane resin as the polymer elastic body impregnated was distributed in a solid form from both sides of the substrate to an average depth of 150 μm. The impregnation depth is 4.5% on one side.
[0074]
Thereafter, the polyethylene component was dissolved and removed from the impregnated substrate in the same manner as in Example 1 to obtain a sheet-like material having extremely fine fibers.
[0075]
Thereafter, both sides of the sheet-like material impregnated with the resin were applied with dimethylformamide using 200-mesh gravure rolls and dried, and then both surfaces were polished with abrasive paper having a grain size of # 320 to raise the surface fibers. Thereafter, slicing was performed at a half-thickness portion that was not impregnated with the resin, to obtain a leather-like sheet having a suede-like appearance.
[0076]
Further, the obtained leather-like sheet was treated in the same manner as in Example 1 to obtain a dyed suede-like leather-like sheet. Observation of the cross section of the obtained sheet-like material by an electron micrograph confirmed that the impregnated layer in which the polyurethane resin as the polymer elastic body was present was distributed from the surface side to an average depth of 125 μm. The ratio of the fibers of the impregnated layer to the elastic polymer was 32:68, and the fiber weight of the non-impregnated portion where no polyurethane resin was present was 195 g / m 2. Two Met. In the impregnated layer, the ultrafine fibers exist in a fiber bundle state, and the polymer elastic body does not exist inside the fiber bundle, and in the void space of the polymer elastic body surrounding the microfine fiber bundle, The fibers occupied 50% of the space volume.
[0077]
The obtained sheet-like material was hardly stretched in any of the vertical, horizontal, and diagonal directions, and was characterized by a soft material in the bending direction. In addition, it was easy to be deformed by low stress, but the characteristic peculiar to soft natural leather was found to stop elongating after a little elongation. Further, the bending recovery rate was 4%, which was a value with almost no repulsion. The sheet was a very soft, low resilience sheet when held, resembling high quality soft leather. Physical properties are also shown in Table 1.
[0078]
[Example 4]
The same processing as in Example 2 was performed to obtain a leather-like sheet in which the fibers were extremely fine.
[0079]
Further, instead of raising the surface of the obtained leather-like sheet, the elastic polymer layer was applied to the surface in order to obtain a grainy tone.
[0080]
That is, Cu9430NL (100% elongation stress is 600 N / cm Two Of a polyurethane resin (manufactured by Dainichi Seika Kogyo Co., Ltd., solid content concentration 30% by weight) in a mixed solution of dimethylformamide and methyl ethyl ketone (mixing ratio 4: 6) (solid content concentration 15%). 130 g / m per unit area on release paper (AR-74M, thickness 0.25 mm, manufactured by Asahi Roll Co., Ltd.) Two (Wet) and first dried at 100 ° C. for 3 minutes. Next, a polymer elastic material Chrisbon TA265 (100% elongation stress of 245 N / cm Two 20 parts of a cross-linked polyurethane resin, manufactured by Dainippon Ink and Chemicals, Inc., having a solid content of 65% by weight, and a polymer elastic crisbon TA290 (100% elongation stress of 245 N / cm) Two 80 parts of a cross-linked polyurethane resin manufactured by Dainippon Ink and Chemicals, Inc., solids concentration: 45% by weight, 15 parts of Coronate L (isocyanate-based cross-linking agent, manufactured by Nippon Polyurethane Co., Ltd.), and Chrisbon Accel T (cross-linked) 3 g of an accelerator, manufactured by Dainippon Ink and Chemicals, Inc., and 10 parts of dimethylformamide were mixed with a binder solution having a basis weight of 100 g / m 2. Two (Wet), and after laminating the surface of the leather-like sheet material on which the fibers are ultra-fine-treated and impregnated with resin as a laminating surface, dried at 100 ° C. for 30 seconds, and then dried. After aging at 70 ° C. for 48 hours, the resultant was left to cool for 12 hours, and the release paper was separated to obtain a leather-like sheet having a tone of silver having a layer of a polymer elastic material on the surface.
[0081]
Thereafter, a 100% elongational stress is applied to the surface of the sheet having a skin layer, which is 350 N / cm Two After finishing the polyurethane resin with a gravure roll of 200 mesh, a softening agent was applied and rubbing was performed.
[0082]
Observation of the cross section of the obtained leather-like sheet material by an electron micrograph revealed that the impregnated layer in which the polyurethane resin which was a polymer elastic body was present was distributed further below the adhesive layer on the surface side to an average depth of 128 μm. Was confirmed. The ratio of the fibers in the impregnated layer to the elastic polymer was 27:73, and the fiber weight of the non-impregnated portion where no polyurethane resin was present was 266 g / m 2. Two Met. In the impregnated layer, the ultrafine fibers exist in a fiber bundle state, and the polymer elastic body does not exist inside the fiber bundle, and in the void space of the polymer elastic body surrounding the microfine fiber bundle, The fibers occupied 50% of the space volume.
[0083]
Further, this leather-like sheet-like material had a good feeling of buckling, did not easily stretch in any of the vertical and horizontal directions, and exhibited characteristics of a soft material in the bending direction. In addition, it was easy to be deformed by low stress, but the characteristic peculiar to soft natural leather was found to stop elongating after a little elongation. Further, the bending recovery rate was 51%, which was a low value of the repulsive force. The substrate thus obtained, having such characteristics, was a very soft and low resilience material similar to high-grade soft natural leather when held. Physical properties are also shown in Table 1.
[0084]
[Comparative Example 1]
As in Example 1, sea-island type composite fiber having a fineness of 8.0 dtex in which nylon-6 and low-density polyethylene are 50/50 was used, the basis weight was increased, and needle punching was performed at 1,400 needles / cm. Two In the same manner except that the weight was changed to 500 g / m Two , Thickness 1.5mm, apparent density 0.33g / cm Three Was obtained.
[0085]
Next, the polymer elastic material crisbon TF50P used in Example 1 (100% elongation stress was 1080 N / cm Two Unlike Example 1, an impregnating solution (concentration: 15%) obtained by dissolving a polyurethane resin (produced by Dainippon Ink and Chemicals, Inc.) with only dimethylformamide was used to obtain a solution weight of 870 g / m 2. Two And immersed in a 10% aqueous solution of dimethylformamide for wet coagulation. Thereafter, the substrate was sufficiently washed in warm water at 40 ° C. to obtain a polymer elastic body-impregnated base material. At this time, it was confirmed by an electron micrograph that the polyurethane resin as the polymer elastic body impregnated was distributed in all layers in a porous form.
[0086]
Thereafter, the polyethylene component was dissolved and removed from the impregnated substrate in the same manner as in Example 1 to obtain a leather-like sheet having extremely fine fibers.
[0087]
Further, the surface of the obtained leather-like sheet was subjected to a surface treatment in the same manner as in Example 1 to obtain a napped and dyed suede-like leather-like sheet. Observation of the cross section of the obtained sheet-like material by an electron microscope photograph confirmed that the polyurethane resin as a polymer elastic body was present in all layers of the sheet. The ratio of the fiber to the elastic polymer was 66:34, and there was no unimpregnated portion where no polyurethane resin was present.
[0088]
Although the obtained sheet-like material was soft in the bending direction and was easily deformed with low stress, it was a material with a strong rebound of 79% in the bending recovery rate, and was the same as conventional soft artificial leather. It was texture. Physical properties are also shown in Table 1.
[0089]
[Comparative Example 2]
In order to make the polymer elastic body softer, instead of the impregnating solution used in Comparative Example 1, polymer elastic body crisbon TF50P (100% elongation stress was 1080 N / cm Two Polyurethane resin, manufactured by Dainippon Ink and Chemicals, Inc., solid content concentration 30% by weight) and polymer elastic material Rezamine Cu 9430NL (100% elongation stress is 600 N / cm Two Of a polyurethane resin (manufactured by Dainichi Seika Kogyo Co., Ltd., solid content concentration: 30% by weight) in a ratio of 30:70 in dimethylformamide (concentration: 13%). / M Two In the same manner as in Comparative Example 1, a leather-like sheet having extremely fine fibers was prepared.
[0090]
Further, the surface of the obtained leather-like sheet was subjected to surface treatment on both sides in the same manner as in Example 3 to obtain a suede-like leather-like sheet having naps on both sides. Then, by slicing at half the thickness, a leather-like sheet having a suede-like appearance was obtained.
[0091]
Further, the obtained leather-like sheet was treated in the same manner as in Example 3 to obtain a dyed suede-like leather-like sheet. Observation of the cross section of the obtained sheet-like material by an electron micrograph confirmed that the polyurethane resin as a polymer elastic body was present in all layers of the base material. The ratio of the fibers to the elastic polymer was 71:29, and there was no unimpregnated portion where no polyurethane resin was present. Although this sheet was very soft in the bending direction, it was a material with a strong rebound of a bending recovery rate of 85% despite its low stretch resistance. Physical properties are also shown in Table 1.
[0092]
[Comparative Example 3]
The same as in Example 1, except that a sea-island composite fiber having a fineness of 9.0 dtex in which nylon-6 and low-density polyethylene were 50/50 was used, and the basis weight was 370 g / m 2 except that the basis weight was lowered. Two , Thickness 1.4mm, apparent density 0.26g / cm Three Was obtained.
[0093]
Next, this non-woven fabric was treated with a polymer elastic material crisbon TF50P / crisbon TF300TD (100% elongation stress was 2750 N / cm). Two Polyurethane resin, manufactured by Dainippon Ink and Chemicals, Inc., solid content concentration: 30% by weight) = impregnated solution (solid content concentration: 15%) dissolved in 6/4 dimethylformamide. The basis weight is 920 g / m Two The excess impregnating liquid is squeezed so as to obtain a polymer elastic material crisbon TF50P / crisbon TF700S (100% elongation stress is 340 N / cm). Two Polyurethane resin, manufactured by Dainippon Ink and Chemicals, Inc., solid content concentration 30% by weight) = 750 g / m2 wet coating solution (solid content concentration 20%) dissolved in 9/1 dimethylformamide. Two The surface was coated so that Next, the sheet made of the fiber and the elastic polymer is immersed in a 12% aqueous solution of dimethylformamide and wet-coagulated, washed sufficiently in warm water of 40 ° C., and dried in a hot air chamber of 135 ° C. A base material having a skin layer made of a polymer elastic body on a base material made of sea-island fibers and a polymer elastic body was obtained. Each of the polymer elastic bodies here has a porous structure having continuous porosity by wet coagulation, and the polyurethane resin, which is a polymer elastic body impregnated, is distributed in all layers in a porous form. Was confirmed by electron micrographs.
[0094]
Thereafter, the polyethylene component was dissolved and removed from the obtained base material in the same manner as in Example 1 to obtain a sheet-like material composed of ultrafine fibers and a porous polymer elastic material. Further, after embossing the surface having the skin layer of the obtained sheet-like material to give a grain pattern, the 100% elongation stress was 350 N / cm. Two Was applied with a 200-mesh gravure roll, a softener was applied, and rubbing was performed.
[0095]
Observation of the cross-section of the obtained sheet-like material having a silver surface with an electron microscope photograph confirmed that the polyurethane resin as a polymer elastic body was present in all layers of the cross-section. The ratio of the fiber to the elastic polymer was 39:61, and there was no unimpregnated portion where no polyurethane resin was present. This sheet-like material is a hard material that has a firm feeling in the bending direction but has a stiffness, but lacks softness, and has a fold recovery rate of 83%, which is a material with strong resilience. Was not so good. Further, fuzz derived from the ultrafine fibers of the impregnated layer was generated on the surface, and the surface quality was low. Physical properties are also shown in Table 1.
[0096]
[Comparative Example 4]
370 g / m of sea-island fiber Two , Thickness 1.4mm, apparent density 0.26g / cm Three Was produced in the same manner as in Comparative Example 3.
[0097]
Next, using the same impregnation solution (solid content: 15%) as that used in Comparative Example 1, the impregnation solution weight was 920 g / m 2. Two In the same manner as in Comparative Example 1, except that the above conditions were satisfied, a leather-like sheet material having ultra-fine fibers was produced by impregnating and extracting.
[0098]
On the other hand, in the same manner as in Example 4, a polymer elastic layer for giving a silver surface tone was applied to the surface by a laminating method. Was finished with a 200-mesh gravure roll, a softener was applied, and rubbing was performed.
[0099]
Observation of the cross section of the obtained silver-finished sheet-like material with an electron micrograph confirmed that the polyurethane resin as a polymer elastic body was present in all layers of the base material. The ratio of the fiber to the elastic polymer was 51:49, and there was no unimpregnated portion where no polyurethane resin was present. The sheet-like material is a hard material having a firm feeling in the bending direction. Although it has a waist, it lacks in softness, and has a bending recovery rate of 83% and has a strong repulsion. Although the feeling of buckling was good, the surface was firm and had a sense of tension. Physical properties are also shown in Table 1.
[0100]
[Table 1]
[Comparative Example 5]
The same basis weight as that of Example 1 450 g / m Two , Thickness 1.5mm, apparent density 0.30g / cm Three Then, the impregnating solution (concentration: 15%) of the polymer elastic material used in Example 1 was repeatedly applied from the surface of the nonwoven fabric to the back side of the base material until it was sufficiently infiltrated. Was dried in a hot-air chamber to obtain a substrate in which all layers of the substrate were impregnated with a polyurethane resin. At this time, it was confirmed by an electron microscope photograph that the polyurethane resin as the polymer elastic body impregnated was distributed in a solid form over the entire base layer.
[0102]
Thereafter, the polyethylene component was dissolved and removed from the substrate in the same manner as in Example 1 to obtain a sheet-like material having extremely fine fibers. The obtained sheet-like material became a very voluminous base having a high rebound, and was different from the soft and low-rebound material which is the object of the present invention.
[0103]
【The invention's effect】
According to the present invention, an artificial leather-like sheet material similar to the physical properties of natural leather that is soft and has low resilience, despite having a strong anti-stretch feeling that could not be possessed by a conventional leather-like sheet material, and The manufacturing method can be provided.
Claims (11)
Priority Applications (9)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002363495A JP4266630B2 (en) | 2002-12-16 | 2002-12-16 | Method for producing leather-like sheet |
| CNB03819306XA CN100436703C (en) | 2002-08-22 | 2003-08-21 | Imitation leather sheet and its manufacturing method |
| KR1020057001528A KR101027365B1 (en) | 2002-08-22 | 2003-08-21 | Leather sheet-like article and its manufacturing method |
| US10/525,204 US20060008631A1 (en) | 2002-08-22 | 2003-08-21 | Leather-like sheet and process for production thereof |
| PCT/JP2003/010594 WO2004018766A1 (en) | 2002-08-22 | 2003-08-21 | Leather-like sheet and process for production thereof |
| EP03792781A EP1550767A4 (en) | 2002-08-22 | 2003-08-21 | Leather-like sheet and process for production thereof |
| TW92123055A TW200413122A (en) | 2002-08-22 | 2003-08-21 | Leather-like sheet and process for production thereof |
| TW98100353A TW200936843A (en) | 2002-08-22 | 2003-08-21 | Leather like sheet material and method for production the same |
| US11/587,593 US7442429B2 (en) | 2002-08-22 | 2005-04-26 | Grain-finished artificial leathers |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002363495A JP4266630B2 (en) | 2002-12-16 | 2002-12-16 | Method for producing leather-like sheet |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2004197232A true JP2004197232A (en) | 2004-07-15 |
| JP4266630B2 JP4266630B2 (en) | 2009-05-20 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2002363495A Expired - Fee Related JP4266630B2 (en) | 2002-08-22 | 2002-12-16 | Method for producing leather-like sheet |
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| JP (1) | JP4266630B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008120702A1 (en) * | 2007-03-30 | 2008-10-09 | Kuraray Co., Ltd. | Leather-like sheet bearing grain finish and process for producing the same |
| WO2017043322A1 (en) * | 2015-09-07 | 2017-03-16 | セーレン株式会社 | Nubuck-like artificial leather, and method for producing nubuck-like artificial leather |
| WO2021049413A1 (en) * | 2019-09-10 | 2021-03-18 | 株式会社クラレ | Napped artificial leather |
-
2002
- 2002-12-16 JP JP2002363495A patent/JP4266630B2/en not_active Expired - Fee Related
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2008120702A1 (en) * | 2007-03-30 | 2008-10-09 | Kuraray Co., Ltd. | Leather-like sheet bearing grain finish and process for producing the same |
| JP5159764B2 (en) * | 2007-03-30 | 2013-03-13 | 株式会社クラレ | Silvered leather-like sheet and method for producing the same |
| US8883662B2 (en) | 2007-03-30 | 2014-11-11 | Kuraray Co., Ltd. | Leather-like sheet bearing grain finish and process for producing the same |
| KR101523394B1 (en) * | 2007-03-30 | 2015-05-27 | 가부시키가이샤 구라레 | For both silver and silver-based leather and a method for producing the same |
| WO2017043322A1 (en) * | 2015-09-07 | 2017-03-16 | セーレン株式会社 | Nubuck-like artificial leather, and method for producing nubuck-like artificial leather |
| JPWO2017043322A1 (en) * | 2015-09-07 | 2017-12-28 | セーレン株式会社 | Nubuck-like artificial leather and method for producing nubuck-like artificial leather |
| EP3333309A4 (en) * | 2015-09-07 | 2019-01-02 | Seiren Co., Ltd | Nubuck-like artificial leather, and method for producing nubuck-like artificial leather |
| WO2021049413A1 (en) * | 2019-09-10 | 2021-03-18 | 株式会社クラレ | Napped artificial leather |
| JPWO2021049413A1 (en) * | 2019-09-10 | 2021-03-18 | ||
| JP7638214B2 (en) | 2019-09-10 | 2025-03-03 | 株式会社クラレ | Raised artificial leather |
| US12571158B2 (en) | 2019-09-10 | 2026-03-10 | Kuraray Co., Ltd. | Napped artificial leather |
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| JP4266630B2 (en) | 2009-05-20 |
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