JP3613711B2

JP3613711B2 - Laminated body

Info

Publication number: JP3613711B2
Application number: JP16807193A
Authority: JP
Inventors: 英夫磯田
Original assignee: Toyobo Co Ltd
Current assignee: Toyobo Co Ltd
Priority date: 1993-07-07
Filing date: 1993-07-07
Publication date: 2005-01-26
Anticipated expiration: 2020-01-26
Also published as: JPH0723834A

Description

【０００１】
【産業上の利用分野】
本発明は、家具、ベッド、車両用クッション材等に適した軽量でクッション性のよい積層構造体に関する。
【０００２】
【従来の技術】
現在、家具、ベッド、電車、自動車等のクッション材で、発泡ウレタン、非弾性捲縮繊維詰綿、及び非弾性捲縮繊維を接着した樹脂綿や硬綿などが使用されている。
【０００３】
しかしながら、高密度の発泡−架橋型ウレタンはクッション材としての耐久性は良好でかつ、安価だが、通気性が悪く、蓄熱性があるため蒸れやすい。他方、密度を下げると耐久性が低下してくる問題がある。
【０００４】
ポリエステル繊維を接着剤で接着した樹脂綿、例えば接着剤にゴム系を用いたものとして特開昭６０−１１３５２号公報、特開昭６１−１４１３８８号公報、特開昭６１−１４１３９１号公報等がある。又、架橋性ウレタンを用いたものとして特開昭６１−１３７７３２号公報等がある。これらのクッション材は耐久性に劣り、且つ、嵩密度も高く、製法は煩雑で加工コストが著しく高いものとなっている。
【０００５】
ポリエステル硬綿、例えば特開昭５８−３１１５０号公報、特開平２−１５４０５０号公報、特開平３−２２０３５４号公報等があるが、用いている熱接着繊維の接着成分が脆い非晶性のポリマ−を用いるため（例えば特開昭５８−１３６８２８号公報、特開平３−２４９２１３号公報等）接着部分が脆く、使用中に接着部分が簡単に破壊されて形態や弾力性が低下するなどの耐久性に劣る問題がある。改良法として、交絡処理する方法が特開平４−２４５９６５号公報等で提案されているが、接着部分の脆さは解決されず、加工コストも高い問題がある。このため、接着部分を柔らかい、且つ変形しても回復するポリエステルエラストマ−を用いた硬綿不織布がＷＯ−９１／１９０３２号公報で提案されている。この繊維構造物に使われる接着成分はポリエステルエラストマ−のハ−ドセグメントの酸成分にイソフタル酸等を含有させ、低融点化させているため非晶性も増し、低溶融粘度として熱接着部分の形成を良くしてアメーバー状の接着部を形成しているが塑性変形しやいため耐熱抗圧縮性が低下する問題点がある。また、熱接着繊維の原料コストや加工コストが非常に高くなる問題がある。
【０００６】
土木工事用に使用する熱可塑性のオレフィン網状体が特開昭４７−４４８３９号公報に開示されている。が、細い繊維から構成したクッションとは異なり表面が凸凹でタッチが悪く、素材がオレフィンのため耐熱耐久性が著しく劣りクッション材には使用ができないものである。この為、改良法として実開平１−１６８４８号公報等に不織布又は織布と積層体化する方法が提案されている。この提案は多数の山部と谷部を持つ網状体に積層されているため、座った時に異物感を感じ座り心地が劣り、座席用クッション材としては不適当なものである。
【０００７】
【発明が解決しようとする課題】
上記従来の問題点を解決し、軽量で安価な、クッション性の優れた座席用に適した積層体を提供することを目的とする。
【０００８】
【課題を解決するための手段】
上記課題を解決するための手段、即ち、本発明は、１００デニール以上の熱可塑性樹脂からなる連続線状体繊維が部分的に融着してなる、見掛け密度が０．０１０ｇ／ｃｍ^３以下の実質的に両面が平坦な網状構造平板体の少なくとも一面に発泡体および／又は不織布が積層一体化されており、見掛け密度が０．０４ｇ／ｃｍ^３以下であることを特徴とする積層体である。
【０００９】
本発明における網状構造体を構成する熱可塑性樹脂としては、ポリエステル、ナイロン、ポリオレフィン、ポリウレタン等が例示できるが、ガラス転移点温度が比較的高いポリエステルが好ましい。ポリエステルからなる繊維としては、例えば、ポリエチレンテレフタレ−ト（ＰＥＴ）、ポリエチレンナフタレ−ト（ＰＥＮ）、ポリシクロヘキシレンジメチレンテレフタレ−ト（ＰＣＨＤＴ）、ポリブチレンテレフタレ−ト（ＰＢＴ）、ポリアリレ−ト等、及びそれらの共重合ポリエステル、ブロック共重合ポリエ−テルエステルやポリエステルエステルなどから選ばれた重合体からなる繊維がある。ＰＥＮやＰＣＨＤＴ等はガラス転移点温度が高く塑性変形しにくいので好ましく、ブロック共重合ポリエ−テルエステルやポリエステルエステルなど弾性樹脂からなる繊維は回復性が良好なので特に好ましい。これらのポリエステル繊維の繊度や繊維断面形状、力学特性などは所望する用途から決められるが、繊度は１００〜１０００００デニ−ル、好ましくは５００〜１００００デニ−ルである。断面形状は特に限定されないが、断面２次モ−メントが高くなることで曲げ剛さが改善される中空断面、多角形あるいは多葉形等の異形断面が好ましい。
【００１０】
本発明の積層構造体を構成する網状構造体は、熱可塑性樹脂からなる繊維が、通常、ループを描いて積層され、該繊維同士が接触部分で融着して実質的に両面が平坦な３次元網状構造を形成している。このことで、大きい応力を付与しても面全体で応力を把持できるので変形しにくく、ガラス転移点温度が高い熱可塑性樹脂では塑性変形しにくく形態保持性に優れたクッション基盤層の機能を発現するので好ましい。また、両面が実質的に平坦化しているので、表面に積層された発泡体又は、及び不織布が柔らかな場合でも臀部に凹凸の異物感を感じない。該繊維同士が接触部分で融着していない場合は、少し大きい応力を与えると容易に変形して座屈してしまうため形態保持性が劣り好ましくない。また、実質的に表面が平坦ではないので、表面に発泡体又は、及び不織布が積層されていても座ると繊維が動き異物感を受ける。本発明のより好ましい融着の程度は、繊維が接触している部分の大半が融着した状態であり、もっとも好ましくは接触部分が全て融着した状態である。
【００１１】
本発明の熱可塑性樹脂からなる連続線状態繊維が、部分的に融着してなる網状構造体の見掛け密度は０．１０ｇ／ｃｍ^３以下である。見掛け密度が０．１０ｇ／ｃｍ^３を越えると弾発性が強くなり、座り心地が悪くなるのだけでなく、座席の軽量化が困難となるので好ましくない。好ましい見掛け密度は０．０１ｇ／ｃｍ^３以上０．０８ｇ／ｃｍ^３以下、より好ましくは０．０１〜０．０５ｇ／ｃｍ^３である。なお、網状構造体の厚みは、特に限定されないが、クッション体としての機能が発現されやすい３ｍｍ以上とするのが好ましい。
【００１２】
本発明の積層体は前記網状構造体の少なくとも一面を発泡体及び、又は不織布と積層一体化することで、座った時、直接臀部がやや硬い風合いの網状構造体と接触せずにタッチの柔らかな発泡体及び、又は不織布で適度の沈み込みによるクッション性を与え、床つき感を緩和することができる。本考案の積層体は、スプリングと接する裏面を補強用不織布で積層し、表面はタッチの柔らかな硬綿不織布と、その上に側地を積層しその下層に発泡体などを積層すると、蒸れを緩和でく、且つ適度の沈み込みによるクッション性を与え、床つき感を抑えることができるので好ましい。表面はタッチの柔らかな弾性繊維を含む硬綿不織布と弾性繊維からなる網状体間及び硬綿不織布とその上の側地間を弾性ポリエステル系の熱接着繊維を含む不織布で積層熱接着して一体化するか、少し硬い網状構造体と弾性繊維からなるソフトな網状構造体間、及びソフトな網状構造体と側地間に弾性ポリエステル系熱接着繊維を含む不織布を積層接着したものがより好ましい。積層する硬綿不織布も弾性ポリエステル系熱接着繊維を含むものとすることで耐熱耐久性とクッション性がより向上するので特に好ましい実施形態である。通常公知の非弾性熱可塑性樹脂系熱接着繊維を用いる場合は出来るだけ非晶性の乏しい熱接着成分を使ったものを用いるのが好ましい。なお、本考案で言う不織布とは、公知の方法で得られるスパンボンド、メルトブロ−で得られる交絡処理をしたまたは、交絡させないで接着した長繊維不織布および、短繊維を開繊後、スパンレ−ス、ニ−ドルパンチ等の交絡処理または、レジンボンド、熱接着繊維で接着処理した熱接着不織布や抄紙法で得られる不織布を含む。なお、熱接着不織布には、厚みの厚い硬綿不織布や、熱接着繊維のみからなる熱接着繊維等を含む。又発泡体とはポリウレタンの様な独立気泡または連通気泡の発泡体を含む。なお、これらの不織布や発泡体の見掛け密度は０．０１〜０．０４ｇ／ｃｍ^３を用いる事で一体積層体の見掛け密度を低くできるので好ましい。本考案の一体化した積層体の見掛け密度は０．０４ｇ／ｃｍ^３以下である。見掛け密度は０．０４ｇ／ｃｍ^３以上では、ポリウレタンの座部の見掛け密度０．０５ｇ／ｃｍ^３より軽量化できないので好ましくない。本考案の好ましい見掛け密度は０．０３５ｇ／ｃｍ^３以下、０．０１ｇ／ｃｍ^３以上である。
【００１３】
網状構造体は直接作ることができコストが安価であり、連通気泡の発泡体のコストも比較的安価である。これらと、少しコストの高い不織布とを組み合わすことで、コストの高い硬綿不織布に較べ、比較的安価なコストでクッション材に適した一体積層体を提供することができる。
【００１４】
熱可塑性樹脂から成る網状構造体の製法は、一般的な溶融押出機を用いて溶融した例えば特開昭５５−１２０６２６号公報等の公知の方法で得た熱可塑性弾性樹脂を複数のオリフィスを持つノズルより下向きに吐出させ、自然落下させると吐出線条が旋回してル−プを形成する。このときノズル面と樹脂を固化させる冷却媒体上に設置した引取りコンベアとの距離、樹脂の溶融粘度、オリフィスの孔径と吐出量などによりループ径と線径がきまる。次いで、冷却媒体上に設置した間隔が調整可能な一対の引取りコンベアで溶融状態の吐出線条を挟み込み停留させることで互いに接触した部分を融着させ、連続して冷却媒体中に引込み固化させ網状構造体を形成する。前記コンベアの間隔を調整することで、融着した網状体が溶融状態でいる間で厚み調節が可能となり、所望の厚みのものが得られる。コンベア速度が速すぎると、融着するまでに冷却され、接触部が融着されなくなる。また、速度が遅過ぎると溶融物が滞留し過ぎ、密度が高くなるので、所望の見掛け密度に適したコンベア速度を設定する必要がある。熱可塑性樹脂を直接網状構造体にすることで、安価にクッション素材を作ることができる。本考案の最も好まし実施形態として弾性樹脂からなる網状構造体を用いる場合、次いで、疑似結晶化処理を行う。この処理は、冷却媒体の温度をアニ−リング温度とすることで冷却と同時に疑似結晶化処理を行うことができる。また、一旦冷却後、乾燥工程を経する場合、乾燥温度をアニ−リング温度とすることで同時に疑似結晶化処理を行うができる。また、別途疑似結晶化処理を行うができる。次いで所望の長さに切断してクッション材に用いる。疑似結晶化処理温度は、少なくとも融点（Ｔｍ）より１０℃以上低く、Ｔａｎδのα分散立ち上がり温度（Ｔαｃｒ）以上で行う。この処理で、融点以下に吸熱ピ−クを持ち、疑似結晶化処理しないもの（吸熱ピ−クを有しないもの）より耐熱耐へたり性が著しく向上する。本発明の好ましい疑似結晶化処理温度は（Ｔαｃｒ＋１０℃）から（Ｔｍ−２０℃）である。網状構造体をクッション層に用いる場合、その使用目的、使用部位により使用する樹脂、繊度、ル−プ径、嵩密度を選択する必要がある。例えば、表層のワディング層に用いる場合は、ソフトなタッチと適度の沈み込みと張りのある膨らみを付与するために、低密度で細い繊度、細かいル−プ径にするのが好ましく、中層のクッション層としては、共振振動数を低くし、適度の硬さと圧縮時のヒステリシスを直線的に変化させて体型保持性を良くし、耐久性を保持させるために、中密度で太い繊度、やや大きいル−プ径が好ましい。また、３次元構造を損なわない程度に成形型等を用いて使用目的にあった形状に成形して使用できる。また、製造過程から成形体に加工する任意の段階で難燃化、防虫抗菌化、耐熱化、撥水撥油化、着色、芳香等の機能付与を薬剤添加等の処理加工ができる。
【００１５】
本発明の一体積層体は、上記製法で得た網状構造体に発泡体及び、または不織布と積層一体化して得られる。不織布は公知の方法で得ることができる。また、熱可塑性エラストマ−からなる不織布についても、例えば、特開昭６３−１２７４６号公報等による製法からはスパンボンド不織布が、特開平３−１１９１６４号公報等による製法でメルトブロー不織布を得ることができる。また、短繊維不織布としては、特願平４−３４０４８３号公報、特願平４−３４２５７７号公報等の方法でエラストマ−系熱接着繊維を用いた耐熱耐久性の良い硬綿不織布を得ることができる。本発明の好ましい実施形態としては、表面から、不織布−エラストマ−系熱接着繊維を用いた耐熱耐久性の良い硬綿不織布−エラストマ−からなるメルトブロ−不織布−連通孔を持つ発泡体−エラストマ−からなるメルトブロ−不織布−網状構造体−エラストマ−からなるメルトブロ−不織布−補強用ポリエチレンテレフタレ−ト（ＰＥＴ）のスパンボンド不織布と積層し、必要な厚みに圧縮し、エラストマ−からなるメルトブロ−不織布の融点より１０℃から２５℃高い温度で熱成形して一体化するか、側地を除いて一体化後、側地を取付けて座席とすることができる。このようにエラストマ−で熱接着一体化することで、変形させても構造が回復して形態保持性が著しく良好となる。しかして、熱接着せずに積層して、側地で積層構造体を覆い一体化されてもよい。また、成形型等を用いて使用目的にあった形状に成形して使用できる。また、製造過程から成形体に加工する任意の段階で難燃化、防虫抗菌化、耐熱化、撥水撥油化、着色、芳香等の機能付与を薬剤添加等の処理加工ができる。
【００１６】
【実施例】
以下に実施例で本発明を詳述する。
【００１７】
なお、実施例中の評価は以下の方法で行った。
▲１▼見掛け嵩密度
平板の試料は１５ｃｍ×１５ｃｍの大きさに切断し、４か所の高さを測定し、体積を求め、試料の重さを体積で徐した値で示す。（ｎ＝４の平均値）座席に成形した試料は、成形体の型取りをして体積を求め、成形座席の重さを体積で徐した値で示す。
▲２▼乗り心地
一体積層体化した座部を自動車の座席フレ−ムにセットし、パネラ−５人に各４時間運転させて以下の点を官能評価させ、５人の平均値で評価した。
（１）床つき感：なし（良）、少しあり（小）、ややあり（中）、著しい（大）
（２）蒸れ感：なし、少し感じる（小）、やや感じる（中）、著しい（大）
（３）クッション性：良好（◎）、２時間位苦にならない（○）、振動が感じられるが１時間位我慢できる（△）、直接振動を感じ３０分も我慢できない（×）
【００１８】
実施例
ジメチルテレフタレ−ト（ＤＭＴ）と１・４ブタンジオ−ル（１・４ＢＤ）を少量の触媒と仕込み、常法によりエステル交換後、分子量２０００のポリテトラメチレングリコ−ル（ＰＴＭＧ）を５８重量％添加して昇温減圧しつつ重縮合せしめ、融点１７９℃、Ｔαｃｒ５８℃のポリエ−テルエステルブロック共重合エラストマ−を生成させ、次いで抗酸化剤１％を添加混合練込み後ペレット化し、５０℃４８時間真空乾燥して得られた熱可塑性弾性樹脂原料を幅５０ｃｍ、長さ５ｃｍのノズル有効面に孔径０．５ｍｍのオリフィスを孔間ピッチ５ｍｍ間隔で配列したノズルより、単孔吐出量を２ｇ／分にて吐出させ、ノズル面５０ｃｍ下に冷却水を配し、幅６０ｃｍのステンレス製エンドレスネットを平行に５ｃｍ間隔で一対の引取りコンベアを水面上に一部出るように配した上に引取り、接触部分を融着させつつ、両面を挟み込みつつ毎分１ｍの速度で７０℃に加熱した冷却水中へ引込み固化させつつ、疑似結晶化処理した後、所定の大きさに切断して見掛け密度０．０４ｇ／ｃｍ^３の網状構造体（網状構造体Ｎｏ．Ａ−１）を得た。
【００１９】
固有粘度０．６３のＰＥＴを２８５℃にて単孔吐出量を２．５ｇ／分とし、ノズル面５０ｃｍ下に冷却水を配し、幅６０ｃｍのステンレス製エンドレスネットを平行に５ｃｍ間隔で一対の引取りコンベアを水面上に一部出るように配した上に引取り、接触部分を融着させつつ、両面を挟み込みつつ毎分１ｍの速度で２０℃の冷却水中へ引込み固化させた後、所定の大きさに切断して見掛け密度０．０５ｇ／ｃｍ^３の網状構造体（網状構造体Ｎｏ．Ａ−２）を得た。
【００２０】
メルトインデクス５０のポリプロピレン（ＰＰ）を幅５０ｃｍ、長さ５ｃｍのノズル有効面に孔径０．５ｍｍのオリフィスを孔間ピッチ５ｍｍ間隔で配列したノズルより、単孔吐出量を１０ｇ／分にて吐出させ、ノズル面５０ｃｍ下に冷却水を配し、幅６０ｃｍのステンレス製エンドレスネットを平行に５ｃｍ間隔で一対の引取りコンベアを水面上に一部出るように配した上に引取り、接触部分を融着させつつ、両面を挟み込みつつ毎分１ｍの速度で２０℃の冷却水中へ引込み固化させた後、所定の大きさに切断して見掛け密度０．２２ｇ／ｃｍ^３の網状構造体（網状構造体Ｎｏ．Ａ−３）を得た。
【００２１】
メルトインデクス５０のポリプロピレン（ＰＰ）を幅５０ｃｍ、長さ５ｃｍのノズル有効面に孔径０．５ｍｍのオリフィスを孔間ピッチ５ｍｍ間隔で配列したノズルより、単孔吐出量を２ｇ／分にて吐出させ、ノズル面５０ｃｍ下に冷却水を配し、幅６０ｃｍのステンレス製エンドレスネットを平行に５ｃｍ間隔で一対の引取りコンベアを水面下になるように配した上に引取り、接触部分を融着させずに、両面を挟み込みつつ毎分１ｍの速度で２０℃の冷却水中へ引込み繊維を固化させて融着しない見掛け密度０．０４ｇ／ｃｍ^３の網状形態の構造体（網状構造体Ｎｏ．Ａ−４）を得た。
【００２２】
Ａ−１で用いたポリエ−テルエステルブロック共重合エラストマ−を鞘成分に、ポリエチレンテレフタレ−ト（ＰＥＴ）を芯成分（５０／５０重量比）にして常法により得た４デニ−ルの熱接着繊維と、固有粘度０．６３のＰＥＴを用い、常法により得た立体捲縮を有する繊度６デニ−ル、初期引っ張り抵抗度４０ｇ／デニ−ル、中空断面の短繊維を３０／７０重量比混繊し、カ−ドにて開繊−積層後、圧縮して２０５℃の熱風で５分間接着処理後、一旦冷却し、次いで５０％圧縮して、１００℃の熱風にて１５分間疑似結晶化処理して得た見掛け密度０．０２ｇ／ｃｍ^３のエラストマ−系熱接着繊維を用いた耐熱耐久性の良い硬綿不織布（不織布Ｎｏ．Ｂ−１）を得た。
【００２３】
ＤＭＴとヘキサンジオール（ＨＤ）及び１・４ＢＤを少量の触媒と仕込み、常法によりエステル交換後、分子量３０００のＰＴＭＧを７８重量％添加して昇温減圧しつつ重縮合せしめ、融点１４２℃のポリエ−テルエステルブロック共重合エラストマ−を生成させ、次いで抗酸化剤１％を添加混合練込み後ペレット化し、４０℃４８時間真空乾燥して得られた熱可塑性弾性樹脂原料を常法により、目付け１０ｇ／ｍ^２のメルトブロー不織布（不織布Ｎｏ．Ｃ−１）を得た。
【００２４】
多数の穴が開けられた座部メス金型に上記網状構造体上に側地を止める金具と共に不織布Ｃ−１／市販の見掛け密度０．０２の連通孔を有する発泡ポリウレタン／不織布Ｃ−１／不織布Ｂが積層されるように重ね、多数の穴が開けられた座部オス金型にて圧縮し、不織布Ｃの融点より１０℃高い熱風で５分間処理して座部形態の一体成形された積層体を得た。次いで座席フレ−ムに側地を被せた積層体を取付け、座り心地と耐久性を評価した。比較のため、網状構造体のみ座席形態としたものを作成し、同様に座席に取付け評価した。積層体の構成及び評価結果を表１に示す。
【００２５】
【表１】

【００２６】
本発明の要件を満たす実施例１及び実施例２は床つき感が無く、蒸れにくく、クッション性の良好な座席に適した積層体であった。比較例１は高密度の網状構造体を用いた例で、発泡体を用いているため、床つき感、蒸れ感、クッション性は良いが座席の密度が高くなり、座席としては好ましくないものである。比較例２は網状構造体が融着していないため、臀部に異物感を感じてクッション性が劣るものである。この座席は形態保持性、耐久性も劣るもとなる。
【００２７】
【発明の効果】
本発明の積層体は、床つき感がなく、蒸れにくく座り心地の良好なクッション材に適した積層体のため、車両用座席に使用しても長時間の運転が快適にでき、安価なため汎用性があり、車両用座席以外にも船舶用座席、家具用クッション、寝装用品の詰め綿等に有用である。
【図面の簡単な説明】
【図１】本発明の積層体の断面を示す図である。
【符号の説明】
１は網状構造体、２は発泡体、３は不織布、４は接着不織布を示す。[0001]
[Industrial application fields]
The present invention relates to a lightweight and cushioning laminated structure suitable for furniture, beds, vehicle cushioning materials, and the like.
[0002]
[Prior art]
Currently, foamed urethane, non-elastic crimped fiber-filled cotton, and resin cotton or hard cotton bonded with non-elastic crimped fibers are used as cushion materials for furniture, beds, trains, automobiles, and the like.
[0003]
However, high-density foam-crosslinked urethane has good durability as a cushioning material and is inexpensive, but is poorly breathable and heat-storable, so it is easily stuffy. On the other hand, when the density is lowered, there is a problem that durability is lowered.
[0004]
Resin cotton in which polyester fibers are bonded with an adhesive, for example, those using a rubber system as an adhesive include JP-A-60-11352, JP-A-61-141388, JP-A-61-141391, and the like. is there. Japanese Patent Application Laid-Open No. 61-137732 discloses a crosslinkable urethane. These cushion materials are inferior in durability, have a high bulk density, have a complicated manufacturing method, and have a very high processing cost.
[0005]
Polyester hard cotton, for example, Japanese Patent Application Laid-Open No. 58-31150, Japanese Patent Application Laid-Open No. 2-154050, Japanese Patent Application Laid-Open No. 3-220354, and the like. -(For example, JP-A-58-136828, JP-A-3-249213, etc.) The adhesive part is fragile, and the adhesive part is easily broken during use, resulting in a decrease in form and elasticity. There is an inferior problem. As an improved method, a method of entanglement treatment has been proposed in JP-A-4-245965 and the like, but there is a problem that the brittleness of the bonded portion is not solved and the processing cost is high. For this reason, WO-91 / 19032 has proposed a hard cotton non-woven fabric using a polyester elastomer that softens the bonded portion and recovers even when deformed. The adhesive component used in this fiber structure contains isophthalic acid in the acid component of the hard segment of the polyester elastomer and has a low melting point. Although the formation is improved to form an amoeba-like adhesive portion, there is a problem in that the heat resistance and compression resistance is lowered due to easy plastic deformation. In addition, there is a problem that the raw material cost and processing cost of the thermal bonding fiber become very high.
[0006]
Japanese Unexamined Patent Publication No. 47-44839 discloses a thermoplastic olefin network used for civil engineering work. However, unlike a cushion composed of thin fibers, the surface is uneven and the touch is poor, and since the material is olefin, the heat resistance is extremely poor and cannot be used as a cushion material. For this reason, a method for forming a laminate with a nonwoven fabric or a woven fabric has been proposed as an improved method in Japanese Utility Model Laid-Open No. 1-1648. Since this proposal is laminated on a net having a large number of peaks and valleys, it feels like a foreign object when sitting, and is not suitable as a cushioning material for seats.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to solve the above-mentioned conventional problems and provide a lightweight and inexpensive laminate suitable for a seat having excellent cushioning properties.
[0008]
[Means for Solving the Problems]
Means for solving the above-mentioned problem, that is, the present invention, an apparent density of 0.010 g / cm ³ or less, in which continuous linear fibers made of a thermoplastic resin of 100 denier or more are partially fused. A laminated body characterized in that a foam and / or nonwoven fabric is laminated and integrated on at least one surface of a network-structured flat body having substantially flat surfaces, and an apparent density is 0.04 g / cm ³ or less. .
[0009]
Examples of the thermoplastic resin constituting the network structure in the present invention include polyester, nylon, polyolefin, polyurethane and the like, but polyester having a relatively high glass transition temperature is preferable. Examples of the fiber made of polyester include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycyclohexylenedimethylene terephthalate (PCHDT), polybutylene terephthalate (PBT), There are fibers made of polymers selected from polyarylate and the like, and their copolyesters, block copolyesters and polyester esters. PEN, PCHDT, and the like are preferable because they have a high glass transition temperature and are difficult to be plastically deformed, and fibers made of an elastic resin such as a block copolymerized polyester ester or polyester ester are particularly preferable because they have good recoverability. The fineness, fiber cross-sectional shape, mechanical properties and the like of these polyester fibers are determined depending on the desired application, and the fineness is 100 to 100,000 denier, preferably 500 to 10,000 denier. The cross-sectional shape is not particularly limited, but a hollow cross-section, a polygonal cross-section, or a multi-lobed cross-section whose bending stiffness is improved by increasing the cross-section secondary moment is preferable.
[0010]
In the network structure constituting the laminated structure of the present invention, fibers made of a thermoplastic resin are usually laminated in a loop, and the fibers are fused together at the contact portion. A three-dimensional network structure is formed. This makes it possible to hold the stress across the entire surface even when a large amount of stress is applied, making it difficult to deform, and a thermoplastic resin with a high glass transition temperature that is difficult to plastically deform and exhibits the function of a cushion base layer with excellent shape retention. This is preferable. Moreover, since both surfaces are substantially flattened, even when the foam or the nonwoven fabric laminated on the surface is soft, there is no sense of uneven foreign matter on the heel. In the case where the fibers are not fused at the contact portion, if a little large stress is applied, the shape is easily deformed and buckled. Moreover, since the surface is not substantially flat, even if a foam or a nonwoven fabric is laminated on the surface, the fibers move and receive a foreign object feeling when sitting. A more preferable degree of fusion of the present invention is a state in which most of the portions in contact with the fibers are fused, and most preferably, the contact portions are all fused.
[0011]
The apparent density of the network structure formed by partially fusing the continuous line fiber made of the thermoplastic resin of the present invention is 0.10 g / cm ³ or less. When the apparent density exceeds 0.10 g / cm ³ , the elasticity becomes strong and not only the seating comfort is deteriorated, but also the weight reduction of the seat becomes difficult, which is not preferable. Preferred apparent density 0.01 g / cm ³ or more 0.08 g / cm ³ or less, more preferably 0.01 to 0.05 g / cm ^3. In addition, the thickness of the network structure is not particularly limited, but is preferably 3 mm or more in which a function as a cushion body is easily expressed.
[0012]
The laminated body of the present invention has a structure in which at least one surface of the network structure is laminated and integrated with a foam and / or a non-woven fabric, so that when sitting down, the buttocks are not directly in contact with the network structure having a slightly hard texture and the touch is soft. The cushioning property by moderate sinking can be given with a simple foam and / or non-woven fabric, and the feeling of flooring can be alleviated. The laminated body of the present invention is laminated with a non-woven fabric for reinforcement on the back surface in contact with the spring, the surface is laminated with a soft cotton nonwoven fabric with a soft touch, and a side fabric is laminated on it, and foam is laminated on the lower layer. It is preferable because it can be relaxed and can provide cushioning by moderate sinking, and can suppress a feeling of flooring. The surface is laminated and bonded together with a nonwoven fabric containing elastic polyester-based heat-bonding fibers between the nonwoven fabric containing soft elastic fibers of touch and the nets made of elastic fibers, and between the nonwoven fabric and the side fabrics on it. More preferably, a non-woven fabric containing elastic polyester-based heat-bonding fibers is laminated and bonded between a soft network structure made of a slightly hard network structure and elastic fibers, and between a soft network structure and a side ground. Since the hard cotton nonwoven fabric to be laminated also includes an elastic polyester-based heat-bonding fiber, the heat resistance and cushioning properties are further improved, which is a particularly preferable embodiment. When using a generally known non-elastic thermoplastic resin-based heat-bonding fiber, it is preferable to use a heat-bonding component having as little amorphous property as possible. The non-woven fabric referred to in the present invention is a spun bond obtained by a known method, a long fiber non-woven fabric that has been entangled by melt blow or bonded without entanglement, and a short fiber after opening, Including a tangled treatment such as a needle punch, a heat-bonded non-woven fabric bonded with a resin bond or a heat-bonded fiber, or a non-woven fabric obtained by a papermaking method. The heat-bonded nonwoven fabric includes thick hard cotton nonwoven fabric, heat-bonded fibers composed only of heat-bonded fibers, and the like. The foam includes a closed-cell or open-cell foam such as polyurethane. In addition, since the apparent density of an integral laminated body can be made low by using 0.01-0.04 g / cm < ³ > for the apparent density of these nonwoven fabrics and foams, it is preferable. The apparent density of the integrated laminate of the present invention is 0.04 g / cm ³ or less. Apparent density is not preferable because the 0.04 g / cm ³ or more, can not be lighter than the apparent density 0.05 g / cm ³ of the seat of polyurethane. Preferred apparent density of the present invention is 0.035 g / cm ³ or less, 0.01 g / cm ³ or more.
[0013]
The net-like structure can be made directly, and the cost is low. The cost of the open cell foam is also relatively low. By combining these with a slightly expensive non-woven fabric, it is possible to provide an integrated laminate suitable for a cushioning material at a relatively low cost compared to a high-cost hard cotton non-woven fabric.
[0014]
A method for producing a network structure made of a thermoplastic resin has a plurality of orifices made of a thermoplastic elastic resin obtained by a known method such as Japanese Patent Application Laid-Open No. 55-120626, which is melted using a general melt extruder. When discharged downward from the nozzle and allowed to fall naturally, the discharge filament turns to form a loop. At this time, the loop diameter and the wire diameter are determined by the distance between the nozzle surface and the take-up conveyor installed on the cooling medium for solidifying the resin, the melt viscosity of the resin, the hole diameter and the discharge amount of the orifice, and the like. Next, a pair of take-up conveyors that are adjustable on the cooling medium can be adjusted so that the molten discharge wire is sandwiched and stopped so that the parts that are in contact with each other are fused and continuously drawn into the cooling medium and solidified. A network structure is formed. By adjusting the interval of the conveyor, the thickness can be adjusted while the fused mesh is in a molten state, and a desired thickness can be obtained. When the conveyor speed is too high, the cooling is performed until the conveyor is fused, and the contact portion is not fused. Further, if the speed is too slow, the melt stays too much and the density becomes high, so it is necessary to set a conveyor speed suitable for the desired apparent density. A cushion material can be made at low cost by directly forming a thermoplastic resin into a network structure. In the case of using a network structure made of an elastic resin as the most preferred embodiment of the present invention, a pseudo crystallization treatment is then performed. In this process, the temperature of the cooling medium is set to the annealing temperature, so that the pseudo crystallization process can be performed simultaneously with the cooling. Moreover, when it passes through a drying process once after cooling, a pseudo crystallization process can be performed simultaneously by making drying temperature into annealing temperature. In addition, a pseudo crystallization process can be performed separately. Next, it is cut into a desired length and used as a cushioning material. The pseudo-crystallization temperature is at least 10 ° C. lower than the melting point (Tm) and is equal to or higher than the Tan dispersion α dispersion rising temperature (Tαcr). By this treatment, the heat sag resistance is remarkably improved from those having an endothermic peak below the melting point and not having a pseudo crystallization treatment (no endothermic peak). The preferred pseudocrystallization temperature of the present invention is from (Tαcr + 10 ° C.) to (Tm−20 ° C.). When the network structure is used for the cushion layer, it is necessary to select the resin to be used, the fineness, the loop diameter, and the bulk density depending on the purpose of use and the site of use. For example, when used as a surface wadding layer, it is preferable to have a low density, fine fineness, and fine loop diameter in order to give a soft touch, moderate subsidence, and a tight bulge. The layer has a medium density, a large fineness, and a slightly larger lure to lower the resonance frequency, linearly change the appropriate hardness and hysteresis during compression to improve body shape retention, and maintain durability. -The diameter is preferred. Further, it can be used after being molded into a shape suitable for the purpose of use using a molding die or the like as long as the three-dimensional structure is not impaired. Further, at any stage of processing from a manufacturing process to a molded body, it is possible to perform processing such as addition of chemicals to impart functions such as flame retardancy, insecticidal and antibacterial properties, heat resistance, water and oil repellency, coloring and aroma.
[0015]
The monolithic laminate of the present invention is obtained by laminating and integrating a foam and / or a non-woven fabric on the network structure obtained by the above production method. The nonwoven fabric can be obtained by a known method. Further, as for the nonwoven fabric made of thermoplastic elastomer, for example, a spunbond nonwoven fabric can be obtained from a production method according to Japanese Patent Laid-Open No. 63-12746, and a melt blown nonwoven fabric can be obtained by a production method according to Japanese Patent Laid-Open No. 3-119164. . Moreover, as a short fiber nonwoven fabric, it is possible to obtain a hard cotton nonwoven fabric having good heat resistance and durability using an elastomer-based heat-bonding fiber by a method such as Japanese Patent Application Nos. 4-340483 and 4-34277. it can. As a preferred embodiment of the present invention, from the surface, from a nonwoven fabric-elastomer-based heat-resistant and durable cotton nonwoven fabric-elastomer melt-bloom-nonwoven fabric-foam with communication holes-elastomer Melt blown nonwoven fabric-network structure-melt blown nonwoven fabric made of elastomer-laminated with spunbond nonwoven fabric of polyethylene terephthalate (PET) for reinforcement, compressed to the required thickness, and melt blown nonwoven fabric made of elastomer It can be integrated by thermoforming at a temperature 10 ° C. to 25 ° C. higher than the melting point, or after integration with the exception of the side ground, the side ground can be attached to form a seat. Thus, by heat bonding and integration with an elastomer, the structure is recovered even when deformed, and the form retainability is remarkably improved. Therefore, the laminated structure may be integrated by covering the laminated structure with the side ground without being thermally bonded. Further, it can be used after being molded into a shape suitable for the purpose of use using a molding die or the like. Further, at any stage of processing from a manufacturing process to a molded body, it is possible to perform processing such as addition of chemicals to impart functions such as flame retardancy, insecticidal and antibacterial properties, heat resistance, water and oil repellency, coloring and aroma.
[0016]
【Example】
The present invention is described in detail below with reference to examples.
[0017]
In addition, evaluation in an Example was performed with the following method.
(1) An apparent bulk density flat plate sample is cut into a size of 15 cm × 15 cm, measured at four heights to determine the volume, and the weight of the sample is shown as a value that is gradually reduced by volume. (Average value of n = 4) For the sample molded on the seat, the molded body is molded, the volume is obtained, and the weight of the molded seat is indicated by a value that is gradually reduced by the volume.
(2) Set the seat with the ride comfort integrated laminate on the seat frame of the car, let the panelists drive for 4 hours each, sensory evaluate the following points, and evaluate with the average value of 5 people .
(1) Feeling with the floor: None (good), some (small), some (medium), remarkable (large)
(2) Feeling of stuffiness: None, feel a little (small), feel a little (medium), noticeable (large)
(3) Cushioning property: good (◎), does not become painful for about 2 hours (○), feels vibration but can endure for about 1 hour (△), feels direct vibration and can not stand for 30 minutes (×)
[0018]
EXAMPLE Dimethyl terephthalate (DMT) and 1.4 butanediol (1.4BD) were charged with a small amount of catalyst, and after transesterification by a conventional method, polytetramethylene glycol (PTMG) having a molecular weight of 2000 was converted to 58 Polyester ester block copolymer elastomer having a melting point of 179 ° C. and a Tαcr of 58 ° C. is formed by adding a weight% and depressurizing and raising the temperature, and then adding 1% antioxidant, kneading and pelletizing. A single-hole discharge amount is obtained from a nozzle in which orifices having a hole diameter of 0.5 mm are arranged on a nozzle effective surface having a width of 50 cm and a length of 5 cm on the effective surface of the thermoplastic elastic resin obtained by vacuum drying at 48 ° C. for 48 hours at intervals of 5 mm between holes. Discharge at 2 g / min, dispose cooling water under 50 cm of nozzle surface, and take a pair of stainless endless nets with a width of 60 cm at intervals of 5 cm The conveyor is placed on the surface of the water so that it is partly drawn, and the contact portion is fused, while the both sides are sandwiched, while the both sides are sandwiched, it is drawn into the cooling water heated to 70 ° C. at a rate of 1 m / min and solidified. After the crystallization treatment, it was cut into a predetermined size to obtain a network structure (network structure No. A-1) having an apparent density of 0.04 g / cm ³ .
[0019]
PET with an intrinsic viscosity of 0.63 is 285 ° C. with a single-hole discharge rate of 2.5 g / min, cooling water is placed under 50 cm of the nozzle surface, and a pair of stainless endless nets with a width of 60 cm are arranged in parallel at intervals of 5 cm. The take-up conveyor is arranged so as to partially come out on the surface of the water, and the contact part is fused, and the both sides are sandwiched and drawn into 20 ° C. cooling water at a speed of 1 m / min. To obtain a network structure (network structure No. A-2) having an apparent density of 0.05 g / cm ³ .
[0020]
A single-hole discharge rate of 10 g / min is discharged from a nozzle in which polypropylene having a melt index of 50 (PP) is arranged on an effective surface of a nozzle having a width of 50 cm and a length of 5 cm with orifices having a hole diameter of 0.5 mm at intervals of 5 mm. Cooling water is placed under 50 cm of the nozzle surface, and a stainless steel endless net with a width of 60 cm is taken in parallel with a distance of 5 cm between the pair of take-up conveyors so as to partially come out on the water surface, and the contact portion is melted. While being worn, both sides are sandwiched and drawn into cooling water at 20 ° C. at a rate of 1 m / min and solidified, then cut into a predetermined size and an apparent density of 0.22 g / cm ³ (network structure) No. A-3) was obtained.
[0021]
A single-hole discharge rate of 2 g / min is discharged from a nozzle in which an orifice having a hole diameter of 0.5 mm is arranged on the effective surface of a nozzle having a width of 50 cm and a length of 5 cm, with an interval of 5 mm between the holes. Cooling water is placed under 50 cm of the nozzle surface, and a stainless steel endless net with a width of 60 cm is taken in parallel with a distance of 5 cm between the pair of take-up conveyors so as to be under the water surface, and the contact portion is fused. In addition, a net-like structure having an apparent density of 0.04 g / cm ³ that does not melt by pulling the fibers into cooling water at 20 ° C. at a speed of 1 m per minute while sandwiching both surfaces (network structure No. A- 4) was obtained.
[0022]
4 denier obtained by a conventional method using the polyester ester block copolymer elastomer used in A-1 as a sheath component and polyethylene terephthalate (PET) as a core component (50/50 weight ratio). Using heat-bonded fibers and PET with an intrinsic viscosity of 0.63, a fineness of 6 denier having a three-dimensional crimp obtained by a conventional method, an initial tensile resistance of 40 g / denier, and a hollow fiber short fiber of 30/70 Mixed by weight, spread with card-laminated, compressed, bonded with hot air at 205 ° C for 5 minutes, cooled once, then compressed 50%, then compressed with hot air at 100 ° C for 15 minutes A hard cotton nonwoven fabric (nonwoven fabric No. B-1) having an excellent heat resistance and durability using an elastomer-based heat-bonding fiber with an apparent density of 0.02 g / cm ³ obtained by pseudo-crystallization treatment was obtained.
[0023]
DMT, hexanediol (HD) and 1.4BD were charged with a small amount of catalyst, and after transesterification by a conventional method, 78% by weight of PTMG having a molecular weight of 3000 was added, and polycondensation was carried out while raising the temperature and reducing the pressure. -Terester block copolymer elastomer was produced, then 1% antioxidant was added, kneaded, pelletized, and vacuum-dried at 40 ° C for 48 hours. / M ² melt blown nonwoven fabric (nonwoven fabric No. C-1) was obtained.
[0024]
Non-woven fabric C-1 / Polyurethane foam / nonwoven fabric C-1 / having a continuous hole with a commercially available apparent density of 0.02 together with metal fittings that stop the side ground on the above-mentioned network structure in a seat female die with a large number of holes The nonwoven fabric B was stacked so as to be laminated, compressed with a seat male mold having a large number of holes, and treated with hot air 10 ° C. higher than the melting point of the nonwoven fabric C for 5 minutes to integrally form the seat configuration. A laminate was obtained. Next, a laminated body with a side cover was attached to the seat frame, and sitting comfort and durability were evaluated. For comparison, only the mesh structure was made into a seat form, and was similarly attached to the seat and evaluated. Table 1 shows the structure of the laminate and the evaluation results.
[0025]
[Table 1]

[0026]
Example 1 and Example 2 satisfying the requirements of the present invention were laminates suitable for seats having no feeling of flooring, less stuffiness, and good cushioning properties. Comparative Example 1 is an example using a high-density network structure, and because it uses a foam, the feeling of flooring, stuffiness, and cushioning are good, but the seat density is high, which is not preferable as a seat. is there. In Comparative Example 2, since the network structure is not fused, the heel portion feels a foreign body and the cushioning property is inferior. This seat is inferior in form retention and durability.
[0027]
【The invention's effect】
The laminate of the present invention is a laminate suitable for a cushioning material that does not feel flooring and is not stuffy and has a good seating comfort, so that it can be comfortably operated for a long time even when used for a vehicle seat and is inexpensive. It is versatile and useful for ship seats, furniture cushions, padding for bedding, etc. in addition to vehicle seats.
[Brief description of the drawings]
FIG. 1 is a view showing a cross section of a laminate according to the present invention.
[Explanation of symbols]
1 is a network structure, 2 is a foam, 3 is a nonwoven fabric, and 4 is an adhesive nonwoven fabric.

Claims

A continuous linear fiber made of a thermoplastic resin elastomer of 100 denier or more is partially fused, and the both sides are substantially flat with an apparent density of 0.01 g / cm ³ or more and 0.08 g / cm ³ or less. A laminate comprising a foam and / or a nonwoven fabric having communication holes laminated and integrated on at least one surface of a network-structured flat body, and an apparent density of 0.04 g / cm ³ or less.