JP4010866B2 - Dryer canvas for paper machines - Google Patents

Description

【００６６】
（実施例１）
実施例１のドライヤーカンバス１００を、表１に示す仕様に基づいて製作した。
すなわち、経糸１０１に、断面寸法が厚さ０．３０ｍｍ×幅０．４６ｍｍの四角形に内接し、外形が連続する１本の曲線から成り、数学的に定義される正規の楕円の断面積に対する断面積比が０．８６の断面積を有する「厚さ方向に直線部のない断面形状」モノフィラメント｛図２（Ｂ）の断面形状２１｝、緯糸１０２に直径寸法が０．７０ｍｍの断面円形ポリエステルモノフィラメントを用い、接紙面側が２／２破れ斜文の緯２重織組織｛図７（Ａ）に示す織組織｝を用いて、経糸充填率１３５．１％、緯糸密度１６．８本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．７９ｍｍ、通気度１２，４６０cm³/ cm²・分であった。
【００６７】
（実施例２）
実施例２のドライヤーカンバス１１０を、表１に示す仕様に基づいて製作した。
すなわち、実施例１と同じ経糸１０１、緯糸１０２および織組織を用いて、経糸充填率１４１．５％、緯糸密度１６．１本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．７７ｍｍ、通気度８，９５０cm³/ cm²・分であった。
【００６８】
（実施例３）
実施例３のドライヤーカンバス１２０を、表１に示す仕様に基づいて製作した。
すなわち、実施例１と同じ経糸１０１、緯糸１０２および織組織を用いて、経糸充填率１４１．８％、緯糸密度１７．６本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．７０ｍｍ、通気度４，４２０cm³/ cm²・分であった。
【００６９】
実施例１〜３では、緯糸に、前記乾熱収縮率の高いモノフィラメントを用いずに、それよりも低い乾熱収縮率（１６０℃で３．８％、１８０℃で７％）のポリエステルモノフィラメントを用いたが、経糸に「厚さ方向に直線部のない断面形状」モノフィラメントを用いたので、経糸充填率を１３５．１％〜１４１．８％とすることができて、カンバス幅方向の表面平滑性が良好となった。また、接紙面側に経糸が長浮きする２／２破れ斜文緯２重織の織組織を用いたので、カンバス流れ方向の表面平滑性も良好、かつ、湿紙への接触面積を増加することが出来た。
【００７０】
【表２】

【００７１】
（実施例４）
実施例４のドライヤーカンバス１３０を、表２に示す仕様に基づいて製作した。
すなわち、実施例１と同じ経糸１０１および織組織を用い、緯糸１０２に直径寸法が０．７０ｍｍの断面円形の乾熱収縮率の高いポリエステルモノフィラメントを用いて、経糸充填率１５２．７％、緯糸密度１７．４本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．７３ｍｍ、通気度４，３００cm³/ cm²・分であった。
【００７２】
（実施例５）
実施例５のドライヤーカンバス１４０を、表２に示す仕様に基づいて製作した。
すなわち、実施例１と同じ経糸１０１および織組織を用い、緯糸１０２に実施例４と同じく直径寸法が０．７０ｍｍの断面円形の乾熱収縮率の高いポリエステルモノフィラメントを用いて、経糸充填率１５３．５％、緯糸密度２２．０本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．７５ｍｍ、通気度１，４９５cm³/ cm²・分であった。
【００７３】
（実施例６）
実施例６のドライヤーカンバス１５０を、表２に示す仕様に基づいて製作した。
すなわち、経糸１０１に、断面寸法が厚さ０．２５ｍｍ×幅０．５０ｍｍの四角形に内接し、外形が連続する１本の曲線から成り、数学的に定義される正規の楕円の断面積に対する断面積比が０．８６の断面積を有する「厚さ方向に直線部のない断面形状」モノフィラメント｛図２（Ｂ）の断面形状２１｝、緯糸１０２に直径寸法が０．６０ｍｍの断面円形の乾熱収縮率の高いポリエステルモノフィラメントを用い、接紙面側が２／２破れ斜文の緯２重織組織｛図７（Ａ）に示す織組織｝を用いて、経糸充填率１５５．０％、緯糸密度２５．５本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．５３ｍｍ、通気度１，３９５cm³/ cm²・分であった。
【００７４】
【表３】

【００７５】
（実施例７）
実施例７のドライヤーカンバス１６０を、表３に示す仕様に基づいて製作した。
すなわち、経糸１６１に、断面寸法が厚さ０．３５ｍｍ×幅０．４６ｍｍの四角形に内接し、外形が連続する１本の曲線から成り、数学的に定義される正規の楕円の断面積に対する断面積比が０．８１の断面積を有する「厚さ方向に直線部のない断面形状」モノフィラメント｛図２（Ｂ）の断面形状２１｝、緯糸１６２に直径寸法が０．７０ｍｍの断面円形の乾熱収縮率の高いポリエステルモノフィラメントを用い、接紙面側が１／３破れ斜文の緯２重織組織｛図７（Ｂ）に示す織組織｝を用いて、経糸充填率１５５．６％、緯糸密度１５．８本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．７７ｍｍ、通気度９，９６８cm³/ cm²・分であった。
【００７６】
（実施例８）
実施例８のドライヤーカンバス１７０を、表３に示す仕様に基づいて製作した。
すなわち、経糸１６１に、断面寸法が厚さ０．３５ｍｍ×幅０．４６ｍｍの四角形に内接し、外形が連続する１本の曲線から成り、数学的に定義される正規の楕円の断面積に対する断面積比が０．８９の断面積を有する「厚さ方向に直線部のない断面形状」モノフィラメント｛図２（Ｂ）の断面形状２１｝、ならびに、実施例７と同じ緯糸１６２および織組織を用いて、経糸充填率１５８．１％、緯糸密度１６．３本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．７９ｍｍ、通気度８，１１０cm³/ cm²・分であった。
【００７７】
実施例４〜８では、経糸に「厚さ方向に直線部のない断面形状」モノフィラメントを用いると共に、緯糸に乾熱収縮率が１６０℃で１２．１％、１８０℃で１９．０％の乾熱収縮率の高いモノフィラメントを用いたので、経糸充填率を１５２．７％〜１５８．１％と実施例１〜３の場合よりも高く出来て、カンバス幅方向の表面平滑性がより良好となった。加えて、実施例４〜６では、接紙面側に経糸が長浮きする２／２破れ斜文緯２重織の織組織を用いたので、カンバス流れ方向の表面平滑性も良好、かつ、湿紙への接触面積を増加させることが出来た。
【００７８】
また、実施例１〜８では、上記の構成により、緯２重の斜文織組織において通気度が１，３９５cm³/ cm²・分〜１２，４６０cm³/ cm²・分の範囲の低い通気度を含む広い通気度調整範囲を得ることが確認できた。
【００７９】
（実施例９）
実施例９のドライヤーカンバス１８０を、表３に示す仕様に基づいて製作した。
すなわち、経糸１８１に実施例１と同じ経糸を用い、緯糸１８２に直径寸法が０．８０ｍｍの断面円形の乾熱収縮率の高いポリエステルモノフィラメントを用い、接紙面側に経糸が長浮きする２／２破れ斜文の緯１重織組織｛図８（Ａ）に示す織組織｝を用いて、経糸充填率１３５．６％、緯糸密度１５．５本／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．３３ｍｍ、通気度６，０３０cm³/ cm²・分であった。
【００８０】
【表４】

【００８１】
（実施例１０）
実施例１０のドライヤーカンバス１９０を、表４に示す仕様に基づいて製作した。すなわち、経糸１９１および緯糸１９２に実施例９と同じ経糸および緯糸を用い、接紙面側に経糸が長浮きする３／１破れ斜文の緯１重織組織｛図８（Ｂ）に示す織組織｝を用いて、経糸充填率１３９．５％、緯糸密度１５．７本／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．３０ｍｍ、通気度５，８８５cm³/ cm²・分であった。
【００８２】
実施例９〜１０では、経糸に「厚さ方向に直線部のない断面形状」モノフィラメントを用いると共に、緯糸に乾熱収縮率（１６０℃で１２．１％、１８０℃で１９．０％）の乾熱収縮率の高いモノフィラメントを用いたので、経糸充填率を高くすることが出来て、カンバス幅方向の表面平滑性がより良好となった。また、接紙面側に経糸が長浮きする２／２若しくは３／１破れ斜文緯１重織の織組織を用いたので、カンバス流れ方向の表面平滑性も良好、かつ、湿紙への接触面積を増加させることが出来た。
【００８３】
【表５】

【００８４】
（比較例１）
比較例１のドライヤーカンバス３００を、表５に示す仕様に基づいて製作した。すなわち、経糸１０１に直径寸法が０．４０ｍｍの断面円形ポリエステルモノフィラメント、緯糸１０２に直径寸法が０．６０ｍｍの断面円形ポリエステルモノフィラメントを用い、接紙面側が２／２破れ斜文の緯２重織組織｛図７（Ａ）に示す織組織｝を用いて、経糸充填率１３１．３％、緯糸密度１７．４本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．８９ｍｍ、通気度１５，６１２cm³/ cm²・分であった。
【００８５】
（比較例２）
比較例２のドライヤーカンバス３１０を、表５に示す仕様に基づいて製作した。すなわち、経糸１０１に直径寸法が０．３０ｍｍの断面円形ポリエステルモノフィラメント、緯糸１０２に直径寸法が０．６０ｍｍ、乾熱収縮率が１６０℃で１２．１％、１８０℃で１９．０％の乾熱収縮率の高い断面円形ポリエステルモノフィラメントを用い、接紙面側が２／２破れ斜文の緯２重織組織｛図７（Ａ）に示す織組織｝を用いて、経糸充填率１４８．２％、緯糸密度１８．３本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．５９ｍｍ、通気度９，１１４cm³/ cm²・分であった。
【００８６】
比較例２のドライヤーカンバスは、上質紙や塗工用原紙の抄紙のような高度な品位水準が要求される用途の抄紙機乾燥部に従来から使用実績の有る、良好な表面平滑性を有するドライヤーカンバスである。
【００８７】
（比較例３）
比較例３のドライヤーカンバス３２０を、表５に示す仕様に基づいて製作した。すなわち、経糸１０１に寸法が厚さ０．３０ｍｍ×幅０．５５ｍｍの断面四角形ポリエステルモノフィラメント、緯糸１０２に直径寸法が０．８０ｍｍ、乾熱収縮率が１６０℃で１２．１％、１８０℃で１９．０％の乾熱収縮率の高い断面円形ポリエステルモノフィラメントを用い、接紙面側が２／２破れ斜文の緯２重織組織｛図７（Ａ）に示す織組織｝を用いて、経糸充填率１１５．４％、緯糸密度１４．０本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法２．０６ｍｍ、通気度１１，３１０cm³/ cm²・分であった。
【００８８】
【表６】

【００８９】
（比較例４）
比較例４のドライヤーカンバス３３０を、表６に示す仕様に基づいて製作した。すなわち、経糸１０１に寸法が厚さ０．３０ｍｍ×幅０．５５ｍｍの断面四角形ポリエステルモノフィラメント、緯糸１０２に直径寸法が０．７０ｍｍ、乾熱収縮率が１６０℃で１２．１％、１８０℃で１９．０％の乾熱収縮率の高い断面円形ポリエステルモノフィラメントを用い、接紙面側が２／２破れ斜文の緯２重織組織｛図７（Ａ）に示す織組織｝を用いて、経糸充填率１１９．９％、緯糸密度１６．９本×２重／２．５４ｃｍに製作した。製作したドライヤーカンバスは、厚さ寸法１．７６ｍｍ、通気度４，５５０cm³/ cm²・分であった。
【００９０】
なお、比較例３および比較例４のドライヤーカンバスは、例えば、カンバス幅寸法が９ｍ以上、抄速ｍａｘ１，５００ｍ／min.以上の広幅・高速の抄紙機乾燥部に従来から使用実績の豊富なドライヤーカンバスである。
（流れ方向および幅方向の剛性の確認）
上記の実施例１〜１０および比較例１〜４のドライヤーカンバスのカンバス流れ方向（経糸方向）およびカンバス幅方向（緯糸方向）の剛性を前記の図３に示す３点曲げ剛性の試験方法により確認した。
【００９１】
測定は、各カンバスについてサンプル数３にて行い、測定結果を表７に示した。
【００９２】
【表７】

【００９３】
各表において、３点曲げ剛性のＰＳ（もしくはＢＳ）とは、試料に加重を掛けて引っ張り上げる方向がＰＳ（もしくはＢＳ）の場合をＰＳ（もしくはＢＳ）と表現する。したがって、カンバス使用時にシリンダー上で湿紙に押圧している状態は、前記のＢＳ方向に加重を掛けて引っ張り上げる場合に相当する。
【００９４】
経糸方向の３点曲げ剛性の測定結果は、荷重方向がＰＳの場合には、実施例１で８８ｃＮ／３ｃｍ、実施例２で８２ｃＮ／３ｃｍ、実施例３で８７ｃＮ／３ｃｍ、実施例４で１００ｃＮ／３ｃｍ、実施例５で１１０ｃＮ／３ｃｍ、実施例６で５４ｃＮ／３ｃｍ、実施例７で８８ｃＮ／３ｃｍ、実施例８で９２ｃＮ／３ｃｍ、実施例９で９５ｃＮ／３ｃｍ、実施例１０で９７ｃＮ／３ｃｍであった。一方、比較例１では１５０ｃＮ／３ｃｍ、比較例２では９９ｃＮ／３ｃｍ、比較例３では１０１ｃＮ／３ｃｍ、比較例４では１０９ｃＮ／３ｃｍであった。
【００９５】
また、荷重方向がＢＳの場合には、実施例１で８２ｃＮ／３ｃｍ、実施例２で７５ｃＮ／３ｃｍ、実施例３で８３ｃＮ／３ｃｍ、実施例４で９５ｃＮ／３ｃｍ、実施例５で１０８ｃＮ／３ｃｍ、実施例６で５３ｃＮ／３ｃｍ、実施例７で８８ｃＮ／３ｃｍ、実施例８で９２ｃＮ／３ｃｍ、実施例９で９５ｃＮ／３ｃｍ、実施例１０で９７ｃＮ／３ｃｍであった。一方、比較例１では１１７ｃＮ／３ｃｍ、比較例２では７６ｃＮ／３ｃｍ、比較例３では８５ｃＮ／３ｃｍ、比較例４では９６ｃＮ／３ｃｍであった。
【００９６】
したがって、経糸方向の３点曲げ剛性が、緯２重の斜文織組織では１１０ｃＮ／３ｃｍ以下、緯１重の斜文織組織では１００ｃＮ／３ｃｍ以下であり、経糸方向の柔軟性が良好であることが確認された。
【００９７】
さらに、本発明のドライヤーカンバスと、織組織が同じ緯２重の斜文織組織であって、カンバス厚さ方向の寸法が同値で同じ材質のポリエステルモノフィラメントを経糸に用い、ほぼ同等の通気度およびほぼ同等もしくはより小さい経糸充填率を有する従来のドライヤーカンバスとを比較した場合、すなわち、実施例２と比較例２、実施例１と比較例３、もしくは、実施例３および実施例４と比較例４を比較した場合、実施例は比較例よりも経糸方向の３点曲げ剛性が小さく、経糸方向の柔軟性が極めて良好であることが判った。
【００９８】
次に、緯糸方向の３点曲げ剛性の測定結果は、荷重方向がＰＳの場合には、実施例１で９３５ｃＮ／３ｃｍ、実施例２で８８０ｃＮ／３ｃｍ、実施例３で９６９ｃＮ／３ｃｍ、実施例４で１，０７６ｃＮ／３ｃｍ、実施例５で１，２９１ｃＮ／３ｃｍ、実施例６で５０５ｃＮ／３ｃｍ、実施例７で８５７ｃＮ／３ｃｍ、実施例８で８８４ｃＮ／３ｃｍ、実施例９で６０２ｃＮ／３ｃｍ、実施例１０で６０９ｃＮ／３ｃｍであった。一方、比較例１では６２７ｃＮ／３ｃｍ、比較例２では６６２ｃＮ／３ｃｍ、比較例３では８８９ｃＮ／３ｃｍ、比較例４では８６２ｃＮ／３ｃｍであった。
【００９９】
また、荷重方向がＢＳの場合には、実施例１で９２９ｃＮ／３ｃｍ、実施例２で８８１ｃＮ／３ｃｍ、実施例３で９７５ｃＮ／３ｃｍ、実施例４で１，０７４ｃＮ／３ｃｍ、実施例５で１，２８９ｃＮ／３ｃｍ、実施例６で５０４ｃＮ／３ｃｍ、実施例７で８５６ｃＮ／３ｃｍ、実施例８で８８５ｃＮ／３ｃｍ、実施例９で６０２ｃＮ／３ｃｍ、実施例１０で６０９ｃＮ／３ｃｍであった。一方、比較例１では６６５ｃＮ／３ｃｍ、比較例２では６６８ｃＮ／３ｃｍ、比較例３では９３１ｃＮ／３ｃｍ、比較例４では９０３ｃＮ／３ｃｍであった。
【０１００】
したがって、緯糸方向の３点曲げ剛性が、緯２重の斜文織組織では５００ｃＮ／３ｃｍ以上、緯１重の斜文織組織では５００ｃＮ／３ｃｍ以上であり、緯糸方向の剛性が高いことが確認された。
【０１０１】
さらに、本発明のドライヤーカンバスと、織組織が同じ緯２重の斜文織組織であって、カンバス厚さ方向の寸法が同値で同じ材質のポリエステルモノフィラメントを経糸に用い、ほぼ同等の通気度を有する従来のドライヤーカンバスとを比較した場合、すなわち、実施例２と比較例２、実施例１と比較例３、もしくは、実施例３および実施例４と比較例４とを比較した場合、実施例は比較例よりも緯糸方向の３点曲げ剛性が大きく、緯糸方向の３点曲げ剛性が高いことが判った。
（走行安定性の評価）
上記の実施例１〜１０および比較例１〜４のドライヤーカンバスの加熱前および加熱後のズレ角度（θ１，θ２）を前記のズレ角度の試験方法により測定して、カンバス走行時の織組織のズレを推定し、形態安定特性と走行安定性を評価した。
【０１０２】
測定は、各カンバスについてサンプル数３にて行い、測定結果を表８に示した。
【０１０３】
【表８】

【０１０４】
その結果、本発明のドライヤーカンバスと、同じ材質のポリエステルモノフィラメントを経糸に、および、同じ材質の乾熱収縮率の高い断面円形ポリエステルモノフィラメントを緯糸に用い、ほぼ同程度の通気度を有する緯２重の斜文織組織から成る従来のドライヤーカンバスとを比較した場合、すなわち、実施例７および実施例８と比較例２とを比較した場合、加熱前のズレ角度（θ１）は実施例７で１．２°、実施例８で１．１°、比較例２で１．０°、および加熱後のズレ角度（θ２）は実施例７で２．５°、実施例８で２．４°、比較例２で２．６°であり、加熱前および加熱後のズレ角度は共に、実施例は比較例とほぼ同等であった。
【０１０５】
また、本発明のドライヤーカンバスと、織組織が同じ緯２重の斜文織組織であって、カンバス厚さ方向の寸法が同値で同じ材質のポリエステルモノフィラメントを経糸に、および、同じ断面形状で同じ材質の乾熱収縮率の高い断面円形ポリエステルモノフィラメントを緯糸に用い、ほぼ同程度の通気度を有する従来のドライヤーカンバスとを比較した場合、すなわち、実施例４と比較例４とを比較した場合、加熱前のズレ角度（θ１）は実施例４で１．０°、比較例４で１．０°、および加熱後のズレ角度（θ２）は実施例４で２．４°、比較例４で２．５°であって、加熱前および加熱後のズレ角度は共に、実施例は比較例とほぼ同等もしくはより小さな値であった。
【０１０６】
したがって、本発明のドライヤーカンバスは、ほぼ同程度の通気度を有する、従来から使用実績の豊富なドライヤーカンバス（比較例２）と比べて、特には、断面四角形モノフィラメントを経糸に用い、同じ織組織であって、ほぼ同程度の通気度を有する、従来から広幅・高速の抄紙機乾燥部に使用実績の豊富なドライヤーカンバス（比較例４）と比べて、走行時の織組織のズレはほぼ同等であり、形態安定特性と走行安定性に優れることが判った。
（流れ方向および幅方向の表面平滑性の評価）
上記の実施例１〜６および比較例１〜４のドライヤーカンバスの流れ方向（経糸方向）および幅方向（緯糸方向）の静摩擦係数および動摩擦係数を前記の試験方法により測定して、流れ方向および幅方向の表面平滑性を評価した。
【０１０７】
測定は、各カンバスについてサンプル数３にて行い、測定結果を表９に示した。
【０１０８】
【表９】

【０１０９】
その結果、本発明のドライヤーカンバスと、織組織が同じ緯２重の斜文織組織であって、カンバス厚さ方向の寸法が同値で同じ材質のポリエステルモノフィラメント経糸、および、同じ断面形状で同じ材質の断面円形ポリエステルモノフィラメント緯糸を用い、ほぼ同程度の通気度を有する従来のドライヤーカンバスとを比較した場合、すなわち、実施例１と比較例３、もしくは、実施例３と比較例４とを比較した場合、経糸方向の静摩擦係数は、実施例１で０．１７７、実施例３で０．１７０、比較例３で０．２０１、比較例４で０．２００であり、経糸方向の動摩擦係数は、実施例１で０．２５７、実施例３で０．２７８、比較例３で０．２９０、比較例４で０．２８５であり、また、緯糸方向の静摩擦係数は、実施例１で０．１７７、実施例３で０．１８０、比較例３で０．２０７、比較例４で０．２００であり、緯糸方向の動摩擦係数は、実施例１で０．２８５、実施例３で０．２４８、比較例３で０．３１９、比較例４で０．３１１であって、カンバスの流れ方向（経糸方向）およびカンバスの幅方向（緯糸方向）について、静摩擦係数および動摩擦係数共に、実施例は比較例に比べて非常に良好な結果であった。
【０１１０】
また、本発明のドライヤーカンバスと、織組織が同じ緯２重の斜文織組織であって、カンバス厚さ方向の寸法が同値で同じ材質のポリエステルモノフィラメント経糸、および、同じ断面形状で同じ材質の乾熱収縮率の高い断面円形ポリエステルモノフィラメント緯糸を用い、ほぼ同等の通気度を有する従来のドライヤーカンバスとを比較した場合、すなわち、実施例２と比較例２、もしくは、実施例４と比較例４とを比較した場合、経糸方向の静摩擦係数は、実施例２で０．１７５、実施例４で０．１６５、比較例２で０．２０３、比較例４で０．２００、経糸方向の動摩擦係数は、実施例２で０．２８２、実施例４で０．２５４、比較例２で０．２９４、比較例４で０．２８５、緯糸方向の静摩擦係数は、実施例２で０．１７６、実施例４で０．１７３、比較例２で０．２１４、比較例４で０．２００、緯糸方向の動摩擦係数は、実施例２で０．２６８、実施例４で０．２４７、比較例２で０．２７５、比較例４で０．３１１であって、カンバスの流れ方向（経糸方向）およびカンバスの幅方向（緯糸方向）について、静摩擦係数および動摩擦係数共に、実施例は比較例に比べて非常に良好な結果であった。
【０１１１】
したがって、本発明のドライヤーカンバスは、ほぼ同程度の通気度を有する、経糸に断面四角形ポリエステルモノフィラメントを配した表面平滑性が良好な従来のカンバス（比較例３、比較例４）に比べて、さらには、ほぼ同等の通気度を有する、経糸に細い線径の円形断面ポリエステルモノフィラメントを高密度に配した、高度な品位水準が要求される用途に適する従来のカンバス（比較例２）に比べて、流れ方向および幅方向の両方向で優れた表面平滑性を有するカンバスであることが確認された。
【０１１２】
【発明の効果】
本発明によれば、合成繊維織物より成る製紙機械用ドライヤーカンバスにおいて、経糸に、厚さ寸法が幅寸法より小さい四角形に内接し、連続する曲線、または、直線および連続する曲線から成る厚さ方向に直線部の無い断面形状を有し、かつ、前記四角形に内接する正規の楕円形の面積より大きい断面積を有する「厚さ方向に直線部のない断面形状」モノフィラメントを用い、経糸充填率を１３０％〜１７５％という高い範囲内としたので、高度な品位水準が要求される用途において使用実績の有る従来のドライヤーカンバスに比べて表面平滑性に優れ、例えば上質紙や塗工用原紙の抄紙のような高度な品位水準が要求される用途に好適に使用できる製紙機械用ドライヤーカンバスを実現することが出来る。
【０１１３】
さらに、本発明によれば、シングルランのカンバス方式やシリンダーが単列配置された形式の乾燥部に適用可能な厚さも達成可能であると同時に、広幅・高速の抄紙機にも適用可能な広幅・高速の抄紙機乾燥部に使用実績の豊富な従来のドライヤーカンバスに比べて、極めて良好な経糸方向の柔軟性と緯糸方向の充分な剛性を兼ね備え、かつ、例えば、カンバス幅寸法が９ｍ以上、抄速ｍａｘ１，５００ｍ／min.以上の条件を含む優れた形態保持特性や走行安定性、ならびに広い通気度調整範囲を有する製紙機械用ドライヤーカンバスを実現することが出来る。
【０１１４】
加えて、前記「厚さ方向に直線部のない断面形状」モノフィラメントを経糸に用いることにより、経糸１本当たりの強力が少なくとも同じ材質からなる外接四角形の強力の７９％を越え９６％以下の範囲を確保出来るので、１３０％以上１７５％以下の経糸充填率の範囲内で外接四角形との断面積比に相応する経糸充填率に設定することにより、外接四角形の断面形状のモノフィラメントを経糸に用いた場合と同等もしくはそれ以上の経糸方向強力を達成することが可能となる。
【図面の簡単な説明】
【図１】本発明を適用し得るカンバスの織組織の各種形態の経糸方向断面から表した概略説明図を示すもので、
（Ａ）は接紙面側表面において経糸が多く表出する２／２正則斜文や２／２破れ斜文緯２重織の織組織、
（Ｂ）は接紙面側および反接紙面側の経糸が長浮きする３／３正則斜文や３／３破れ斜文、３／３急斜文や３／３急破れ斜文緯２重織の織組織、
（Ｃ）は接紙面側表面において経糸が多く表出する２／１正則斜文や２／１破れ斜文緯１重織の織組織、
（Ｄ）は接紙面側表面において経糸が多く表出する３／１正則斜文や３／１破れ斜文、３／１急斜文や３／１急破れ斜文緯１重織の織組織である。
【図２】（Ａ）は断面形状が楕円形状の経糸の断面図、
（Ｂ）は本発明に係る断面形状を有する経糸の一例の断面図、
（Ｃ）は本発明に係る断面形状を有する経糸の異なる例の断面図、
（Ｄ）は本発明に係る断面形状を有する経糸のさらに他の例の断面図である。
【図３】ドライヤーカンバスの３点曲げ剛性の試験方法の説明図である。
【図４】（Ａ）はドライヤーカンバスのズレ角度測定方法の説明図、
（Ｂ）はドライヤーカンバスのズレ角度測定装置における荷重時の斜視図、
（Ｃ）はドライヤーカンバスのズレ角度測定装置におけるズレ角度測定時の斜視図である。
【図５】ドライヤーカンバスの摩擦係数測定装置の概略構成図である。
【図６】（Ａ）は従来の断面形状が四角形状の経糸を用いたカンバスの接紙面側における要部拡大断面の説明図、
（Ｂ）は本発明の断面形状を有する経糸を用いたカンバスの接紙面側における要部拡大断面の説明図である。
【図７】本発明の実施例および比較例に用いた各織組織の経糸方向断面からの概略説明図を示すもので、
（Ａ）は接紙面側が２／２破れ斜文の緯２重織組織のカンバス織組織、
（Ｂ）は接紙面側が１／３破れ斜文の緯２重織組織のカンバス織組織である。
【図８】本発明の実施例に用いた各織組織の経糸方向断面からの概略説明図を示すもので、
（Ａ）は接紙面側の経糸が長浮きする２／２破れ斜文の緯１重織組織のカンバス織組織、
（Ｂ）は接紙面側の経糸が長浮きする３／１破れ斜文の緯１重織組織のカンバス織組織である。
【符号の説明】
１０，１００，１１０，１２０，１３０，１４０，１５０，１６０，１７０，１８０，１９０，３００，３１０，３２０，３３０ ドライヤーカンバス
１１，１０１，１６１，１８１，１９１ 経糸
１２，１０２，１６２，１８２，１９２ 緯糸
１３ 接紙面側
１４ 反接紙面側
２０ 数学的に定義される正規の楕円形状
２１，２２ 厚さ寸法が幅寸法より小さい四角形に内接し、連続する曲線から成る、かつ、前記四角形に内接する正規の楕円形の面積より大きい断面積を有する断面形状、
２３ 厚さ寸法が幅寸法より小さい四角形に内接し、直線および連続する曲線から成る厚さ方向に直線部の無い、かつ、前記四角形に内接する正規の楕円形の面積より大きい断面積を有する断面形状
３０ 摩擦係数測定装置
５０ ズレ角度測定装置
７０ 経糸
７１ カンバス表面
ＰＳ 接紙面側
ＢＳ 反接紙面側
Ｘ 幅寸法
Ｙ 厚さ寸法
Ｚ 直線部の長さ寸法
ｍ，ｋ，ｌ，ｎ 曲線
ｐ 直線[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of a dryer canvas for a paper machine used in a drying section of a paper machine. In particular, it has excellent shape retention characteristics and running stability that can be applied to wide and high speed paper machines, and has surface smoothness that is suitable for applications that require a high level of quality, and in the warp direction. The present invention relates to a dryer canvas for a papermaking machine having flexibility and rigidity in a weft direction.
[0002]
[Prior art]
The dryer canvas used in the drying section of a paper machine presses wet paper against a heated cylinder and makes it dry by contacting it. However, if the pressing force applied to the wet paper is not uniform, it causes uneven drying and impairs the paper quality. Become. In particular, in applications that require a high quality level, such as high-quality paper and paper for coating base paper, not only does it cause quality defects such as paper marks on wet paper, but also the direction of wet paper flow. In addition, the demand for uniformity of drying in the width direction is severe. Therefore, it is necessary to bring the wet paper into contact with the cylinder uniformly, and it is possible for the dryer canvas to maintain uniform adhesion and pressing force with the wet paper in the flow direction and the width direction even under wide and high speed conditions. Desired. Therefore, it is necessary to have good surface smoothness and flexibility in the warp direction, and at the same time have both strength in the warp direction and rigidity in the weft direction.
[0003]
On the other hand, in recent years, paper machines have become wider and faster. For example, the canvas width is 9m or more and the paper making speed is max 1,500m / min. The dryer canvas that can ensure the stable operation of the paper machine is demanded, and in addition to the conventional dryer canvas, in addition to improving the flexibility in the warp direction and the rigidity in the weft direction Therefore, it has become more important to improve the shape retention characteristics and running stability.
[0004]
On the other hand, the structure of the drying section of the multi-cylinder dryer for papermaking has conventionally been an upper and lower canvas system in a two-stage upper and lower dryer, a single-run canvas system as an improved version thereof, and a cylinder as an improved version thereof. Have been proposed to improve the paper-making speed, such as the Berlan system (trademark of Beloit, USA) and the Simlan system (trademark of Valmet, Finland). In the single run canvas method, the wet paper runs on the outer periphery of the dryer canvas on the lower cylinder on the lower cylinder, and on the suction roller provided between the cylinders in the Berlan method. This causes a difference in peripheral speed corresponding to the thickness of the canvas, and this is the reason why, for example, when a dryer canvas that has been conventionally used in a drying section having dryers of a two-stage upper / lower arrangement is used, As the paper travels, tension on the wet paper is repeatedly tensioned and loosened, which may adversely affect the wet paper and may cause severe defects such as paper breaks. For this reason, it is indispensable that the canvas is thin, particularly in a single-run canvas system that performs high-speed papermaking or a drying section in which the cylinders are arranged in a single row.
[0005]
One way to improve the flexibility in the warp direction of a dryer canvas is to use monofilaments of fineness for the warp that constitutes the canvas. In addition, the canvas is configured to increase the rigidity in the weft direction. It is conceivable to use a monofilament with a large fineness for the weft to be used. Therefore, if a monofilament with finer fineness is used for the warp and a monofilament with larger fineness is used for the weft, it will be possible to improve the flexibility in the warp direction while securing the rigidity in the weft direction. When the warp stiffness is insufficient with respect to the weft stiffness, the warp and weft crossing part is loosely coupled and the binding between the yarns is weakened, resulting in a decrease in canvas resistance. There is a fear.
[0006]
Here, “deviation resistance” is a characteristic representing resistance to deformation of the dryer canvas in an oblique direction. As the deformation of the dryer canvas progresses in the diagonal direction, the dimensional changes in the width direction and length direction increase, causing problems such as the inability to maintain the required form as a dryer canvas and the inability to ensure running stability. Become. Therefore, it is necessary to select the relationship between the fineness of the warp and the fineness of the weft, and the relationship between the stiffness of the warp and the stiffness of the weft.
[0007]
In addition, as another method for improving the flexibility in the warp direction of a dryer canvas, the warp constituting the canvas has an appropriate thickness dimension and a so-called flat monofilament (hereinafter referred to as a cross-sectional monofilament having a width dimension larger than the thickness dimension). There is a method using a "monofilament having a square cross section").
[0008]
In addition, in order to flatten the warp yarns constituting the dryer canvas, a considerable high pressure is applied to the dryer canvas under heating to make a thick thread with a circular cross section into a flat cross section and flatten the knuckle portion (Japanese Patent Laid-Open No. 58-41992), a technique of flattening by polishing a knuckle portion woven with a yarn having a circular cross section (Japanese Utility Model Publication No. 57-56798) has been conventionally used, but generates a high pressure force under heating. There is a problem in that it is necessary to have a facility to be used, and dirt such as paper powder and filler is likely to adhere to the rough surface of the polished warp.
[0009]
By the way, when a monofilament having a square cross section is used for warp, flexibility in the warp direction can be obtained, but it has been found that there are the following problems.
[0010]
That is, with the recent increase in demand for paper quality and higher speed of paper machines, a wide air permeability range including low air permeability is achieved while maintaining high surface smoothness and small thickness. For this reason, there is a limit to the correspondence only with a high-density weft and a weaving structure in which the warp floats for a long time, and the rigidity and configuration in the direction of the weft in order to increase the speed and width of the paper machine. In order to reinforce the holding characteristics, it is necessary to increase the density of the warp. For example, it is necessary to set the filling rate of the warp to a high range exceeding 100%, preferably 125%. Further, it is difficult to secure a desired high filling rate due to interference between the monofilaments having a rectangular cross section, and it is difficult to improve the displacement property, and it is difficult to further improve the shape retention characteristics and the running stability.
[0011]
Furthermore, if the filling rate is increased to a certain extent, the parallel surface of the mono-filament monofilament flat surface and the canvas surface cannot be maintained even if a material having a good surface property is selected for the woven structure {see FIG. 6 (A)}. In a part of the canvas surface, the corner of the square of the cross section of the warp yarn 70 appears on the canvas surface 71, which affects the improvement of the surface property of the canvas, and also affects the weaving of the warp yarn during weaving. It became clear that there was a problem such as causing a decrease in. For example, the applicants experienced the knowledge that a warp filling rate of around 125% is the practical upper limit when using a square polyester polyester monofilament with a thickness dimension × width dimension of 0.30 mm × 0.55 mm for the warp. Have.
[0012]
The warp filling rate is a percentage per unit length expressed using the product of the warp density in the width direction of the fabric and the width dimension in the fabric width direction of the warp cross section.
[0013]
[Problems to be solved by the invention]
In view of the above problems, the present invention has good surface smoothness that can be suitably used in applications that require a high quality level, such as papermaking of high-quality paper and coating base paper, and It is an object of the present invention to provide a dryer canvas for a papermaking machine having both flexibility in the warp direction and rigidity in the weft direction.
[0014]
Furthermore, the thickness can be applied to a single-run canvas system or a drying section of a type in which cylinders are arranged in a single row. For example, the canvas width dimension is 5 m to 9 m, further 9 m or more, the papermaking speed max1, It is an object of the present invention to provide a dryer canvas for a papermaking machine having excellent shape retention characteristics, running stability, and a wide air permeability adjustment range, which can be applied to a wide and high speed paper machine of 500 m / min. Or more.
[0015]
[Means for Solving the Problems]
The dryer canvas for a paper machine of the present invention is a dryer canvas for a paper machine made of a synthetic fiber fabric, and is inscribed in a square having a thickness smaller than a width in a warp, a continuous curve, or a straight line and a continuous A synthetic fiber monofilament having a cross-sectional shape without a straight line portion in the thickness direction composed of a curved line and having a cross-sectional area larger than the area of a regular ellipse inscribed in the quadrangle, and a warp filling rate 130% It is characterized by being in the range of ˜175%.
[0016]
Furthermore, in the dryer canvas for paper machine of the present invention, the synthetic fiber monofilament used for the warp is a quadrangle whose thickness dimension × width dimension is in the range of 0.25 mm to 0.40 mm × 0.35 mm to 0.80 mm. It has a cross-sectional shape having no straight part in the thickness direction inscribed.
[0017]
In addition, in the dryer canvas for papermaking machine according to the present invention, the monofilament having a cross-sectional shape having no straight portion in the thickness direction used for warp has a ratio of thickness dimension: width dimension of 1: 1.25 to 1: 2. It is characterized by having a cross-sectional area inscribed in a square within the range and in a range exceeding 0.79 times and not more than 0.96 times the cross-sectional area of the inscribed square.
[0018]
In the dryer canvas for papermaking machine of the present invention, a monofilament having a high dry heat shrinkage rate is provided on at least one layer of the weft. Using It is characterized by this.
[0019]
Furthermore, the dryer canvas for papermaking machine of the present invention comprises a weft double weave weave structure, and at least the paper contact surface side weft and / or the counter contact surface side weft has a diameter of 0.40 mm to 0.80 mm. A monofilament with a circular cross section inside is used, and the thickness dimension is in the range of 1.30 mm to 1.80 mm.
[0020]
Furthermore, the dryer canvas for papermaking machine of the present invention is composed of a weft monoclinic woven structure in which warp yarns float at least on the surface of the paper contact surface, and the weft yarn has a diameter of 0.60 mm to 1.00 mm. A monofilament having a circular cross section in the range is used, and the thickness dimension is in the range of 1.00 mm to 1.60 mm.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
The dryer canvas for papermaking machine of the present invention is a synthetic fiber fabric woven using synthetic fiber yarns for warp and weft.
[0022]
Synthetic fiber yarns include polyester fibers such as PET and PBT, polyamide fibers such as nylon 6, nylon 46 and nylon 66, polyolefin fibers such as polypropylene, or synthetic fiber yarns made of PPS or PEEK having excellent heat resistance. Alternatively, synthetic fiber yarns mainly composed of them can be used, and they are used alone or in combination for warp and / or weft. Polyester fibers such as PET and PBT are preferable from the viewpoint of dimensional stability, wear resistance, bending fatigue resistance, and PPS and PEEK are preferable from the viewpoint of heat resistance.
[0023]
Weaving structures include warp single weave structures commonly used in dryer canvases, warp double weaves, weft 2.5 double weaves, and oblique weaves of three or more wefts. A double woven structure is applicable. For example, a weft double weave, a weft 2.5 double weave, or a weft triple weave 1/3 regular or 1/3 broken oblique is preferably applicable.
[0024]
Further, it is preferable that the warp is a floating structure to improve the flatness of the surface and increase the contact area to the wet paper in the canvas flow direction, that is, the warp direction, and at least the warp of the warp on the surface of the paper contact surface is long. A double or single weft texture is preferred. The woven structure in which the warp floats long refers to a structure in which the warp straddles two or more wefts, and in the above-described double weft texture structure in which the warp floats long on the surface of the paper contact surface, FIG. A) As shown in (B), 2/2 regular syllabary or 2/2 torn syllabary {FIG. 1 (A)}, 3/3 regular syllabary or 3 A woven structure such as a 3/3 torn text {FIG. 1 (B)}, a 3/3 steep text, or a 3/3 steep torn text {FIG. 1 (B)} can be used. Further, as shown in FIGS. 1 (C) and 1 (D), 2/1 regular slashes and 2/1 broken slashes {FIG. 1 (C)}, in which a large amount of warp is expressed on the surface of the paper contact surface. 3/1 regular and 3/1 broken text {Fig. 1 (D)} 3/1 steep and 3/1 sudden broken text {Fig. 1 (D)} A woven structure can be used.
[0025]
A dryer canvas for a paper machine according to the present invention is a dryer canvas for a paper machine made of a synthetic fiber fabric, and is inscribed in a quadrangle in which a thickness dimension is smaller than a width dimension, and a continuous curve or a straight line and a continuous line. A synthetic fiber monofilament having a cross-sectional shape without a straight line portion in the thickness direction consisting of a curved line and having a cross-sectional area larger than the area of a regular ellipse inscribed in the quadrangle, and a warp filling rate 130% It is characterized by being in the range of ˜175%.
[0026]
Here, “the thickness direction dimension is inscribed in a quadrangle smaller than the width direction dimension and has a continuous curve or a cross-sectional shape having no straight portion in the thickness direction composed of a straight line and a continuous curve, and the square A synthetic fiber monofilament having a cross-sectional area larger than a mathematically defined regular oval area inscribed in “is a cross section having a minor axis a and a major axis b as shown in FIG. In addition to the regular oval shape defined in Fig. 1, in addition to the cross-sectional shape that is simply chamfered at the four corners of the cross-sectional quadrangle, the straight line portion remains in the thickness direction. It is excluded from “a cross-sectional shape without a portion”, and has a cross-sectional shape as shown in FIG. 2 (B), FIG. 2 (C) and FIG. 2 (D). That is, when the outline is constituted by a continuous curve, it is constituted by one or two continuous curves, and when the outline is constituted by a straight line and a continuous curve, one straight line and It has a cross-sectional shape composed of one continuous curve. Moreover, the cross-sectional shape in which the outline does not curve inward and the outline does not have a recess is preferable.
[0027]
That is, FIG. 2B is composed of a single curve m inscribed in a quadrilateral having a width dimension X and a thickness dimension Y, and a continuous curve representing the outer shape in the cross section. Pass through each of the points included in the image, for example, the midpoints c, c ′, d, d ′, closer to the circumscribed rectangle side than the mathematically defined normal ellipse of FIG. The cross-sectional shape has a larger cross-sectional area. Alternatively, FIG. 2C is composed of two curves k and l that are inscribed in a quadrangle having the same width direction X and thickness dimension Y, and in which the curves representing the outer shape in the cross section are continuous, and the curve k is a circumscribed rectangle. Each one point included in three of the four sides, for example, the middle point c, d, c ′, and one point included in three of the four sides of the circumscribed rectangle, for example, the middle point A cross-sectional shape that passes c, d ', and c' and has a larger cross-sectional area that is closer to the circumscribed square side than the regular elliptical shape defined mathematically in FIG. is there. FIG. 2D is a cross-sectional shape that approximates FIG. 2B and has one straight line p at a position that overlaps one curve n and a side (long side) in the width direction of the circumscribed rectangle. The cross-sectional shape is closer to the circumscribed square and has a larger cross-sectional area than the regular elliptical shape defined mathematically in FIG. In this case, the length dimension Z of the linear portion p is preferably 1/2 to 3/4 of the width direction dimension X.
[0028]
Hereinafter, in the present invention, these shapes are abbreviated as “a cross-sectional shape having no straight portion in the thickness direction”.
[0029]
According to the present invention, by using the monofilaments 21 to 23 having the above-mentioned “cross-sectional shape without straight portions in the thickness direction” for the warp of the canvas, for example, as shown in FIG. The side surface of the adjacent monofilament interferes with each other, which has been a problem in the case where the warp 70 shown in FIG. The problem that it was difficult to secure a desired high warp filling rate was solved.
[0030]
As described above, the monofilament having a “cross-sectional shape having no straight portion in the thickness direction” used for the warp yarn of the dryer canvas of the present invention does not include a mathematically defined regular cross-sectional ellipse, and represents a line representing the outer shape of the monofilament. Is closer to the circumscribed quadrangle, the cross-sectional area of the circumscribed quadrangle is X and the thickness dimension is Y. (Cross-sectional area of the quadrangle = XY)>(" No cross-sectional shape ”cross-sectional area)> (mathematical normal cross-sectional elliptical cross-sectional area = πXY / 4≈0.79XY), which is greater than the mathematically defined normal elliptical monofilament. The area is large. Therefore, the strength per yarn can be maintained high, and the strength in the warp direction of the dryer canvas can be maintained high.
[0031]
The range of the cross-sectional area of the monofilament of “cross-sectional shape having no straight portion in the thickness direction” used for the warp yarn of the dryer canvas of the present invention is less than the cross-sectional area (XY) of the circumscribed square as described above, and The range exceeds the inscribed normal elliptical cross-sectional area (≈0.79XY). However, as a preferable range, the cross-sectional area exceeds 0.79XY, and the range is 0.96XY or less, and the minimum value is more preferable. The range is 0.81XY, and the maximum value is 0.89XY.
[0032]
That is, as a cross-sectional shape having a cross-sectional area corresponding to the minimum value, for example, when the ratio of the thickness dimension Y to the width dimension X of the circumscribed square is 1: 1.25, the cross-sectional shape is lower in the thickness direction. The side (or upper side) is a regular elliptical shape mathematically defined, and the upper side (or lower side) in the thickness direction has two corners on the upper side (or lower side) of the circumscribed square. A cross-sectional shape having a cross-sectional area corresponding to a smoothly chamfered shape with a radius corresponding to 2 can be exemplified. In addition, as a cross-sectional shape having a cross-sectional area corresponding to the maximum value, for example, when the ratio of the thickness dimension Y to the width dimension X of the circumscribed square is 1: 2.0, the four corners of the circumscribed square are thickened. A cross-sectional shape having a cross-sectional area corresponding to a shape smoothly chamfered with a radius corresponding to ½ of the dimension can be exemplified. Alternatively, for example, in the cross-sectional shape shown in FIG. 2C, a high-order function (for example, Y = Z · X) passing through the midpoints c, d, and c ′. ^W Where Z is a real number and w is a natural number) and one other continuous curve l that can be expressed by a higher-order function that passes through the midpoints c, d, and c ′. A cross-sectional shape having an outer shape can be exemplified.
[0033]
If a monofilament having a cross-sectional area with no cross-sectional area as exemplified above is used for a warp of a canvas, the strength of a circumscribed square composed of at least the same material is used for the warp of each warp. It is possible to ensure a range exceeding 96% and 96% or less, so that the filling rate of warp is 1 / 0.79 times the upper limit of 125% or 130% in the case of a monofilament with a circumscribed square cross section. Exceeding 1 / 0.96 times, that is, 130% or more, less than 158%, or 137% or more, less than 165%, or 130% or more, less than 165%. If the warp filling rate is set to correspond to the above, it is possible to achieve warp direction strength equivalent to that when a monofilament having a cross-sectional shape of a circumscribed square is used for the warp.
[0034]
Further, preferably, the strength per warp can be secured within a range of 81% or more and 89% or less of the strength of the circumscribed square made of at least the same material. In the range of 1 / 0.89 times or more and 1 / 0.81 times or less than that of a monofilament having a circumscribed square cross section, that is, 140% or more, 154% or less, or 146% or more, 160% or less, or 140% If the warp filling ratio corresponding to the cross-sectional area ratio with the circumscribed square is within the range of 160% or less, the warp direction strength equivalent to that when a monofilament with a circumscribed square cross-section is used for the warp is achieved. Is possible. If the warp filling ratio is set to a range exceeding at least 160%, it is possible to make the warp direction stronger than when a monofilament with a circumscribed square cross section is used for the warp.
[0035]
Note that the upper limit of the warp filling rate is 175% because, depending on the applied woven structure and the rigidity of the monofilament warp, the warp yarns overlap when the warp filling rate is higher than this, and surface smoothness that can be used as a canvas is obtained. This is because it becomes difficult.
[0036]
In practicing the present invention, the thickness dimension × width dimension of the circumscribed rectangle inscribed by the “cross-sectional shape having no straight portion in the thickness direction” used for the warp is 0.25 mm to 0.35 mm × 0.40 mm to 0 Within the range of 70 mm. Furthermore, it is preferable that the ratio of the thickness dimension to the width dimension of the circumscribed square is in the range of 1: 1.25 to 1: 2. The upper limit of 1: 2 is to avoid an excessive tension load per warp during weaving and use due to a decrease in the number of warps in the canvas width direction. Dryer canvas composed of monofilaments for warp and weft is inferior in cushioning properties to those made of multifilament and spun yarn, so the tension in the warp direction during use is set higher than that of In this case, a gearless dryer may be installed in the paper machine drying section. In such a case, the tension load on the canvas is set at a maximum of 3 kg / cm. However, in order to ensure stable operation and durability corresponding to warp wear and thermal degradation, it is necessary to consider so that the tension load per warp is reduced. On the other hand, in order to effectively exhibit the flatness in the cross-sectional width direction of the “cross-sectional shape having no straight portion in the thickness direction”, 1: 1.25 is set as the lower limit.
[0037]
For the weft, a monofilament is used at least on the paper contact surface side and / or the reverse paper contact surface side. As the cross-sectional shape of the weft, a circular shape, an elliptical shape, a polygonal shape such as a triangle, a square, a rectangle, a quadrangle, a hexagon, and an octagon, and a shape obtained by partially changing these shapes can be used. Other wefts include fine-filament monofilaments, multifilament yarns, yarns made of spun or twisted yarns, and covered yarns having a spiral or coiled core-sheath structure, etc. However, from the viewpoint of preventing dirt from being adhered to the canvas with paper dust or filler and removing the adhered dirt, it is preferable that the wetting yarn on the paper contact surface side and the weft yarn on the opposite paper surface side are composed of monofilaments.
[0038]
Furthermore, the dryer canvas for papermaking machine according to the present invention is characterized in that a monofilament with a high dry heat shrinkage rate is used for at least one layer of the weft and the filling rate of warp yarn is within a range of 130% to 175%.
[0039]
In order to increase the filling rate of warps, in addition to setting the warp density during weaving, we will select and use processing conditions that increase the amount of shrinkage in the weft direction during heat setting and high weft shrinkage . When using a weft having a high dry heat shrinkage rate, it is used for at least one weft. The use of all the weft layers can increase the filling rate of the warp. Further, it is preferable to use the weft on the paper contact surface side in order to increase the contact area with the wet paper. When wefts having a high dry heat shrinkage rate are used, it is possible to realize a warp filling ratio in the range of 130% to 175%, preferably in the range of 140% to 175%, more preferably in the range of 150% to 175%. Become.
[0040]
The monofilament having a high dry heat shrinkage used for the weft in the practice of the present invention is in the range of 12% to 26% at 160 ° C, 14% to 30% at 180 ° C, and more preferably 12% to 22% at 160 ° C. , Which has a dry heat shrinkage in the range of 14% to 24% at 180 ° C., and is generally available for dryer canvas. For example, as a polyester monofilament, PX-405 manufactured by Shakespeare is commercially available. Further, PPS monofilaments include those disclosed in JP-A-5-195318.
[0041]
In the practice of the present invention, when the monofilament used for the weft is a weft double weave, a weft 2.5 double weave, or a weft triple or more weave, the paper contact surface side weft and / or the reverse paper surface side weft For example, a circular monofilament having a cross-sectional diameter within a range of 0.30 mm to 1.20 mm can be used for each, but the diameter dimension is within a range of 0.40 mm to 0.80 mm with respect to the size range of the warp. It is desirable to use a monofilament with a circular cross section. Further, with respect to the dimension range of the wefts having a diameter of 0.40 mm to 0.80 mm, the diameter is in the range of 12 x 2 / 2.54 cm to 39 x 2 / 2.54 cm, preferably 13 A weft density in the range of x double / 2.54 cm to 25 x double / 2.54 cm can be applied.
[0042]
In the case of a single weft weave structure, for example, a circular monofilament having a cross-sectional diameter in the range of 0.40 mm to 1.50 mm can be used as the weft, but the diameter dimension is 0.60 mm to 1 It is desirable to use a circular monofilament with a cross-section in the range of 0.000 mm, and for the weft yarn size range of 0.60 mm to 1.00 mm in diameter, 12 / 2.54 cm to 35/2. A weft density in the range of 54 cm, preferably in the range of 15 / 2.54 cm to 30 / 2.54 cm can be applied.
[0043]
Of course, the wefts having different dimensions and / or densities may be used for the paper-contacting surface-side wefts and the paper-contacting surface-side wefts.
[0044]
The lower limit of the above-mentioned weft density is the lower limit value for obtaining the upper limit of the necessary air permeability range while satisfying the surface smoothness, the weft direction rigidity, the running stability, the shape retention, etc., which are necessary for the application used. It is. The upper limit of the weft density is obtained from the upper limit of the number of wefts that can be arranged in the canvas flow direction under the minimum value in the warp and weft dimension range. In order to achieve such a high weft density, tension conditions and temperature conditions at the time of weaving and processing are suitably set appropriately so that the amount of shrinkage in the warp direction at the time of heat setting increases. Furthermore, for example, a monofilament with a high dry heat shrinkage can be selected and used for the warp.
[0045]
In the present invention, using a monofilament having a “cross-sectional shape having no straight portion in the thickness direction” for the warp, 130% Within 175% When Since it can be increased, a good surface smoothness and a wide air permeability range can be achieved in combination with the set range of the weft density, and at the same time, rigidity in the canvas width direction can be secured. . That is, a lower air permeability than before can be realized by a high warp filling rate and a high weft density. Even when a low weft density is taken in order to obtain a high air permeability range, the warp filling rate is high, so that the surface smoothness can be maintained well. Further, the density of contact points on the surface of the paper contact surface that comes into contact with the wet paper becomes high, and the wet paper can be pressed uniformly, so that the occurrence of unevenness in drying of the wet paper can be reduced.
[0046]
The rigidity in the canvas width direction is usually improved as the dimension of the weft yarn in the canvas thickness direction is increased. By arranging and using it so as to be in the width direction, it is possible to make the warp thickness dimension smaller than when using a cross-sectional circular monofilament having an equivalent cross-sectional area for warp, so that the required canvas thickness dimension Since the thickness direction dimension of the weft can be increased within the range, the rigidity in the canvas width direction can be improved accordingly.
[0047]
Furthermore, the present invention uses a “cross-sectional shape having no straight part in the thickness direction” monofilament for the warp so that the warp yarns adjacent to each other in the width direction of the canvas are sufficiently adhered by setting a high filling rate of the warp. Therefore, in combination with the rigidity of the monofilament weft having the above-mentioned diameter size range, the warp yarn has a circular cross-section or a quadrilateral cross-section monofilament. The rigidity in the width direction can be improved as compared with the case where it is used. As a result, it is possible to obtain rigidity in the width direction that can cope with a request for a canvas width dimension of 9 m or more.
[0048]
Further, the present invention provides that when the warp having the above-mentioned “cross-sectional shape without a straight portion in the thickness direction” abuts against the weft having a circular cross-section, the cross-sectional shape formed by a smooth curved surface effectively acts, The thickness of the canvas is reduced by utilizing the fact that the warp can be crossed more deeply at the crossing portion with the weft than when the warp is in contact with the weft having a circular cross section.
[0049]
That is, for example, when a contact force P based on the tension T per unit length applied to the weft acts, a warp having a square cross section abuts on a weft having a circular cross section, In the case where the warp yarn of “cross-sectional shape” is in contact with the weft having a circular cross-section, the area A of the contact portion projected in the canvas thickness direction is smaller in the latter case than in the former case, and the contact force P The rate of change in the size of the area A of the contact portion related to the size of the contact area is larger in the latter case than in the former case, so that the unit area per unit area based on the contact force P and the area A of the contact portion is larger. The contact pressure P becomes larger in the case of a warp having an elliptical cross section, and the warp can be crossed more deeply at the crossing portion with the weft and the thickness of the canvas can be reduced.
[0050]
In the present invention, the warp yarn has a thickness dimension × width dimension of 0.25 mm to 0.35 mm × 0.40 mm to 0.70 mm. Cross-sectional shape without cross section "polyester monofilament, cross-sectional circular polyester monofilament having a diameter of 0.40 mm to 0.80 mm in the weft, a warp filling ratio in the range of 125% to 175%, and a weft density of Based on the results of various trial manufactures of dryer canvas having a weft double oblique weave texture in the range of 12 × double / 2.54 cm to 39 × double / 2.54 cm, the thickness dimension is 1. It was confirmed that a canvas within a range of 30 mm to 1.80 mm was obtained.
[0051]
The warp yarn has a thickness dimension × width dimension of 0.25 mm to 0.35 mm × 0.40 mm to 0.70 mm. Non-cross-sectional polyester monofilaments, cross-sectional circular polyester monofilaments with diameters ranging from 0.60 mm to 1.00 mm, weft filling rates ranging from 125% to 175%, and weft density of 12 Based on the results of various trial productions of dryer canvass having a weft texture of 1 weft with a range of /2.54 cm to 35.0 /2.54 cm, the thickness dimension is 1.00 mm to 1.60 mm It was confirmed that a canvas within the range was obtained.
[0052]
Therefore, according to the present invention, for example, it has good surface smoothness that can be suitably used in applications requiring a high quality level, such as paper making of high-quality paper and coating base paper, and has a warp direction. It is possible to realize a dryer canvas for a papermaking machine that has both flexibility and rigidity in the weft direction.
[0053]
Furthermore, it has a thickness of 1.80 mm or less applicable to a single-run canvas system or a drying section of a type in which cylinders are arranged in a single row, for example, a canvas width dimension of 9 m or more, and a paper making speed max 1,500 m / It is possible to realize a dryer canvas for a papermaking machine that can be applied to a wide and high speed paper machine of min.
[0054]
In addition, about the method of each test concerning implementation of this invention, it is based on the following.
(1) Dry heat shrinkage
Five samples obtained by cutting the raw yarn into a length of 300 mm are treated in a hot air dryer for 20 minutes. The sample taken out is left in a room in a standard state (temperature 20 ° C., relative humidity 65%) for about 30 minutes or more, then its length is measured, and is expressed as an average value of five samples obtained by the following formula.
Dry heat shrinkage (%) = {(300 (mm) −length after treatment (mm)) / 300 (mm)} × 100 (%)
[0055]
▲ 2 ▼ Air permeability
JIS L-1096: 1999 Using a measuring device conforming to the Frazier method used for measurement of air permeability in “General Textile Testing Method”, under a specified pressure (125 Pa) through an air hole having a specified measurement area. The amount of air that passed through the test piece per unit time (1 minute), that is, the air permeability (cm ^Three / cm ² ・ Measure minutes.
[0056]
(3) 3-point bending rigidity
3, the sample 42 having a width of 3 cm (dimension in the front and back direction in FIG. 3) is fixed to the rollers 43, 43 having a diameter of 20 mm fixedly spaced from each other by 100 mm. The part is pulled upward through a round bar 44 having a diameter of 10 mm and a load meter (not shown). The displayed value of the load meter increases with the amount of pulling up of the round bar 44, but the displayed value of the load meter does not increase when it is pulled up to some extent. The maximum load at this time is referred to as a stiffness value and is expressed in the unit cN / 3 cm.
[0057]
When measuring the three-point bending stiffness in the warp direction, the longitudinal direction of the sample 42 (the direction perpendicular to the width dimension 3 cm) is the warp direction, and when measuring the three-point bending stiffness in the weft direction, the longitudinal direction of the sample 42 is The weft direction.
[0058]
(4) Misalignment angle
4 (B) and 4 (C) show a misalignment angle measuring device 50 in which one end of each of the lateral arms 55 and 56 is swingable up and down by a pivot pin 59 at the upper end portion and the base end portion of the fixed column 54, respectively. The other ends of the horizontal arms 55 and 56 are connected in a link shape with a connecting arm 57, and the upper horizontal arm 55 is normally fixed to the fixed horizontal arm 60 with a pin 61. Further, a pointer 58 for instructing the inclination angle is attached to the base of the lateral arm 55 on the upper end side.
[0059]
The upper end of the sample S having a predetermined length and width is fixed by the horizontal arm 55 and the fixed horizontal arm 60, and a load W of 1 kg per 1 cm of the width of the sample S is suspended from the lower end. In this state, the lower end of the sample S is fixed to the lower horizontal arm 56, and then the load W is removed. In this way, the sample S is fixed as shown in FIG. 4B, the pin 61 is pulled out, and a downward moment is applied as shown in FIG. 4C. After leaving in this state for a certain period of time, the displacement dimension x1 (before heating) in FIG. 4A is measured with the pointer 58, and in this state, heat treatment is performed at a temperature of 130 ° C. for a certain period of time. Thereafter, the displacement dimension x2 (after heating) is again measured with the pointer 58.
[0060]
As shown in FIG. 4A, the displacement angles θ1 (before heating) and θ2 (after heating) are calculated as follows: The displacement dimension x obtained from the scale reading at the position where the pointer 58 fixed to the lateral arm 55 crosses. (Mm), the length from the center point of the pivot pin 59 to the tip of the pointer 58 is calculated from L (= 120 mm) by the following equation.
[0061]
tan θ = x / 120, θ = tan−1 (x / 120)
The displacement of the woven structure during the traveling of the dryer canvas is estimated from the displacement angle θ obtained as described above, and is used for evaluating the shape retention characteristics and traveling stability of the dryer canvas.
[0062]
(5) Static friction coefficient and dynamic friction coefficient
FIG. 5 shows a friction coefficient measuring device 30. That is, when the load W is applied in the vertical direction to the sample S by the weight 32 on the fixed contact member 31 as shown in FIG. 5, the wire 33 and the pulley 34 run in the arrow direction (speed 50 mm / min). ), The static friction force F1 at the start of movement, and the dynamic friction force F2 to be moved after the movement starts, and based on the static friction force F1, the dynamic friction force F2 and the load (W = 5 kg) ) = Friction force (F) / Load (W) The static friction coefficient μ1 and the dynamic friction coefficient μ2 were calculated.
[0063]
Sample S is used with a width dimension of 10 cm and a length dimension of 15 cm. When obtaining the friction coefficient in the warp direction, the length direction of the sample is the warp direction, and when obtaining the friction coefficient in the weft direction, the length of the sample is used. The direction is the weft direction. The direction in which the sample S travels is the length direction of the sample.
[0064]
(Example)
Next, the Example of this invention and the comparative example with respect to an Example are demonstrated based on Table 1-Table 6. FIG.
In each table, “TM” represents a polyester monofilament, “PS” represents a paper contact surface side, “BS” represents a reverse paper contact surface side, and “high shrinkage yarn” represents a monofilament having a high dry heat shrinkage rate. Further, the “cross section of the present invention” represents the cross sectional shape of the “filament having no straight portion in the thickness direction” monofilament of the present invention, and the “cross sectional area ratio” represents the cross sectional area ratio with respect to the normal elliptical cross sectional area.
[0065]
[Table 1]

[0066]
Example 1
The dryer canvas 100 of Example 1 was manufactured based on the specifications shown in Table 1.
That is, the warp 101 has a cross-sectional dimension of a thickness of 0.30 mm × width of 0.46 mm. “Cross sectional shape without straight line in the thickness direction” monofilament {Cross sectional shape 21 in FIG. 2 (B)} having a cross-sectional area of 0.86, and a weft 102 having a circular cross-sectional polyester monofilament having a diameter of 0.70 mm 2 is used, and the weft double side weave structure {weave structure shown in FIG. 7A} is used, and the warp filling ratio is 135.1%, the weft density is 16.8 pieces × double. /2.54 cm. The manufactured dryer canvas has a thickness of 1.79 mm and an air permeability of 12,460 cm. ^Three / cm ² ・ It was minutes.
[0067]
(Example 2)
The dryer canvas 110 of Example 2 was manufactured based on the specifications shown in Table 1.
That is, the same warp 101, weft 102 and woven structure as in Example 1 were used to produce a warp filling ratio of 141.5% and a weft density of 16.1 × double / 2.54 cm. The manufactured dryer canvas has a thickness of 1.77 mm and an air permeability of 8,950 cm. ^Three / cm ² ・ It was minutes.
[0068]
(Example 3)
The dryer canvas 120 of Example 3 was manufactured based on the specifications shown in Table 1.
That is, using the same warp 101, weft 102 and woven structure as in Example 1, a warp filling ratio of 141.8% and a weft density of 17.6 × double / 2.54 cm were produced. The produced dryer canvas has a thickness of 1.70mm and air permeability of 4,420cm. ^Three / cm ² ・ It was minutes.
[0069]
In Examples 1 to 3, a polyester monofilament having a lower dry heat shrinkage rate (3.8% at 160 ° C. and 7% at 180 ° C.) than the monofilament having a high dry heat shrinkage rate is not used for the weft. Although used, the warp yarn has a “cross-sectional shape with no straight portion in the thickness direction” monofilament, so that the warp filling ratio can be 135.1% to 141.8%, and the surface smoothness in the canvas width direction can be achieved. The property became good. In addition, since a weaving structure of 2/2 broken oblique weft double weave in which the warp floats long on the paper contact surface side is used, the surface smoothness in the canvas flow direction is good and the contact area with the wet paper is increased. I was able to.
[0070]
[Table 2]

[0071]
(Example 4)
The dryer canvas 130 of Example 4 was manufactured based on the specifications shown in Table 2.
That is, using the same warp 101 and woven structure as in Example 1, and using a polyester monofilament having a circular cross section with a diameter of 0.70 mm and a high dry heat shrinkage as the weft 102, a warp filling rate of 152.7% and a weft density 17.4 × double / 2.54 cm. The manufactured dryer canvas has a thickness of 1.73 mm and an air permeability of 4,300 cm. ^Three / cm ² ・ It was minutes.
[0072]
(Example 5)
The dryer canvas 140 of Example 5 was manufactured based on the specifications shown in Table 2.
That is, using the same warp 101 and woven structure as in Example 1, and using a polyester monofilament having a circular cross-section with a diameter of 0.70 mm and a high dry heat shrinkage as the weft 102 as in Example 4, a warp filling rate of 153. 5%, weft density 22.0 × double / 2.54 cm. The manufactured dryer canvas has a thickness of 1.75mm and air permeability of 1,495cm. ^Three / cm ² ・ It was minutes.
[0073]
(Example 6)
A dryer canvas 150 of Example 6 was manufactured based on the specifications shown in Table 2.
That is, the warp yarn 101 is inscribed in a square with a cross-sectional dimension of 0.25 mm thickness x 0.50 mm width and a continuous outer shape. “Cross sectional shape with no straight part in the thickness direction” monofilament {Cross sectional shape 21 in FIG. 2 (B)} having a sectional area of 0.86, and a weft 102 having a circular sectional shape with a diameter of 0.60 mm. Polyester monofilament with a high thermal shrinkage is used, and the weft density is 155.0% using the double weave structure {woven structure shown in FIG. 25.5 pieces × duplex / 2.54 cm. The manufactured dryer canvas has a thickness of 1.53 mm and an air permeability of 1,395 cm. ^Three / cm ² ・ It was minutes.
[0074]
[Table 3]

[0075]
(Example 7)
The dryer canvas 160 of Example 7 was manufactured based on the specifications shown in Table 3.
That is, the warp 161 has a cross-sectional dimension of 0.35 mm in thickness x 0.46 mm in width and is inscribed in a mathematically defined normal ellipse cross-sectional area consisting of a single curve with a continuous outer shape. “Cross sectional shape with no straight part in the thickness direction” monofilament {Cross sectional shape 21 in FIG. 2 (B)} having a sectional area of 0.81 and a weft 162 having a circular sectional shape with a diameter of 0.70 mm. Polyester monofilament with high heat shrinkage is used, and the weft double weave structure {weave structure shown in FIG. 7B} is 1/3 broken on the paper-contact side, and the weft density is 155.6%. 15.8 pieces × duplex / 2.54 cm. The manufactured dryer canvas has a thickness of 1.77 mm and an air permeability of 9,968 cm. ^Three / cm ² ・ It was minutes.
[0076]
(Example 8)
The dryer canvas 170 of Example 8 was manufactured based on the specifications shown in Table 3.
That is, the warp 161 has a cross-sectional dimension of 0.35 mm in thickness x 0.46 mm in width and is inscribed in a mathematically defined normal ellipse cross-sectional area consisting of a single curve with a continuous outer shape. “Cross sectional shape having no straight portion in the thickness direction” monofilament {Cross sectional shape 21 in FIG. 2 (B)} having a sectional area of 0.89, and the same weft 162 and woven structure as in Example 7 were used. Thus, a warp filling ratio of 158.1% and a weft density of 16.3 pieces × double / 2.54 cm were produced. The manufactured dryer canvas has a thickness of 1.79 mm and an air permeability of 8,110 cm. ^Three / cm ² ・ It was minutes.
[0077]
In Examples 4 to 8, a monofilament having a “cross-sectional shape without a straight portion in the thickness direction” is used for the warp, and the dry heat shrinkage of the weft is 12.1% at 160 ° C. and 19.0% at 180 ° C. Since a monofilament with a high thermal shrinkage was used, the warp filling rate was 152.7% to 158.1%, which was higher than those in Examples 1 to 3, and the surface smoothness in the canvas width direction was improved. It was. In addition, in Examples 4 to 6, since a woven structure of a 2/2 broken oblique weft double weave in which the warp floats long on the paper contact surface side is used, the surface smoothness in the canvas flow direction is good and the wet The contact area with the paper could be increased.
[0078]
Further, in Examples 1 to 8, with the above-described configuration, the air permeability is 1,395 cm in a double weave texture. ^Three / cm ² ・ Minth ~ 12,460cm ^Three / cm ² -It was confirmed that a wide air permeability adjustment range including a low air permeability of a minute range was obtained.
[0079]
Example 9
The dryer canvas 180 of Example 9 was manufactured based on the specifications shown in Table 3.
That is, the same warp as in Example 1 is used for the warp 181, and a polyester monofilament having a circular cross section with a diameter of 0.80 mm and a high dry heat shrinkage is used for the weft 182. Using a weft single weave structure of torn oblique text {woven structure shown in Fig. 8A}, a warp filling ratio of 135.6% and a weft density of 15.5 yarns / 2.54 cm were produced. The manufactured dryer canvas has a thickness of 1.33 mm and an air permeability of 6,030 cm. ^Three / cm ² ・ It was minutes.
[0080]
[Table 4]

[0081]
(Example 10)
The dryer canvas 190 of Example 10 was manufactured based on the specifications shown in Table 4. That is, the same warp and weft as in Example 9 are used for the warp 191 and the weft 192, and the warp single weave structure of the 3/1 broken oblique where the warp floats long on the paper contact surface side {the weave structure shown in FIG. 8B } With a warp filling ratio of 139.5% and a weft density of 15.7 pieces / 2.54 cm. The manufactured dryer canvas has a thickness of 1.30 mm and an air permeability of 5,885 cm. ^Three / cm ² ・ It was minutes.
[0082]
In Examples 9 to 10, a monofilament having a “cross-sectional shape without a straight portion in the thickness direction” is used for the warp, and a dry heat shrinkage (12.1% at 160 ° C., 19.0% at 180 ° C.) is used for the weft. Since a monofilament with a high dry heat shrinkage rate was used, the warp filling rate could be increased and the surface smoothness in the canvas width direction was improved. In addition, a 2/2 or 3/1 broken weft weft weft structure with a long float on the paper contact side is used, so that the surface smoothness in the canvas flow direction is good and the wet paper is contacted. The area could be increased.
[0083]
[Table 5]

[0084]
(Comparative Example 1)
A dryer canvas 300 of Comparative Example 1 was manufactured based on the specifications shown in Table 5. That is, a circular polyester monofilament having a cross-sectional diameter of 0.40 mm is used for the warp yarn 101, and a circular polyester monofilament having a cross-sectional diameter of 0.60 mm is used for the weft yarn 102. Using the woven structure shown in FIG. 7 (A), a warp filling ratio of 131.3% and a weft density of 17.4 × double / 2.54 cm were produced. The manufactured dryer canvas has a thickness of 1.89 mm and air permeability of 15,612 cm. ^Three / cm ² ・ It was minutes.
[0085]
(Comparative Example 2)
The dryer canvas 310 of Comparative Example 2 was manufactured based on the specifications shown in Table 5. That is, the warp yarn 101 has a circular polyester monofilament with a diameter of 0.30 mm, the weft yarn has a diameter of 0.60 mm, and the dry heat shrinkage rate is 12.1% at 160 ° C. and 19.0% at 180 ° C. Using a circular polyester monofilament with a high shrinkage ratio and a weft double weave structure {weave structure shown in FIG. 7 (A)} with 2/2 tearing on the paper-contacting side, weft filling rate is 148.2%, weft The density was 18.3 × double / 2.54 cm. The manufactured dryer canvas has a thickness of 1.59 mm and an air permeability of 9,114 cm. ^Three / cm ² ・ It was minutes.
[0086]
The dryer canvas of Comparative Example 2 is a dryer having a good surface smoothness that has been used in the paper machine drying section for applications that require a high quality level, such as high quality paper and base paper for coating. It is a canvas.
[0087]
(Comparative Example 3)
A dryer canvas 320 of Comparative Example 3 was manufactured based on the specifications shown in Table 5. That is, the warp yarn 101 has a rectangular polyester monofilament having a thickness of 0.30 mm and a width of 0.55 mm, the weft yarn 102 has a diameter of 0.80 mm, a dry heat shrinkage rate of 12.1% at 160 ° C., and 19 at 180 ° C. Using a cross-sectional circular polyester monofilament with a high dry heat shrinkage of 0.0% and using a weft double weave structure {woven structure shown in FIG. It was manufactured to 115.4% and a weft density of 14.0 pieces × double / 2.54 cm. The produced dryer canvas has a thickness of 2.06mm and air permeability of 11,310cm. ^Three / cm ² ・ It was minutes.
[0088]
[Table 6]

[0089]
(Comparative Example 4)
A dryer canvas 330 of Comparative Example 4 was manufactured based on the specifications shown in Table 6. That is, the warp yarn 101 has a square cross-sectional polyester monofilament having a thickness of 0.30 mm and a width of 0.55 mm, the weft yarn has a diameter of 0.70 mm, a dry heat shrinkage rate of 12.1% at 160 ° C, and 19 at 180 ° C Using a cross-sectional circular polyester monofilament with a high dry heat shrinkage of 0.0% and using a weft double weave structure {woven structure shown in FIG. It was manufactured to 119.9% and a weft density of 16.9 pieces × double / 2.54 cm. The manufactured dryer canvas has a thickness of 1.76 mm and air permeability of 4,550 cm. ^Three / cm ² ・ It was minutes.
[0090]
The dryer canvases of Comparative Example 3 and Comparative Example 4 are, for example, dryers that have been used extensively in wide- and high-speed paper machine drying sections with canvas width dimensions of 9 m or more and paper making speeds of max. 1,500 m / min. It is a canvas.
(Confirm rigidity in flow direction and width direction)
The rigidity in the canvas flow direction (warp direction) and the canvas width direction (weft direction) of the dryer canvases of Examples 1 to 10 and Comparative Examples 1 to 4 was confirmed by the test method for the three-point bending rigidity shown in FIG. did.
[0091]
The measurement was performed with 3 samples for each canvas, and the measurement results are shown in Table 7.
[0092]
[Table 7]

[0093]
In each table, PS (or BS) having a three-point bending rigidity is expressed as PS (or BS) when the direction in which the specimen is pulled by applying a weight is PS (or BS). Therefore, the state in which the wet paper is pressed on the cylinder when the canvas is used corresponds to the case where the wet paper is pulled in the BS direction.
[0094]
The measurement results of the three-point bending stiffness in the warp direction are 88 cN / 3 cm in Example 1, 82 cN / 3 cm in Example 2, 87 cN / 3 cm in Example 3, and 100 cN in Example 4 when the load direction is PS. / 3 cm, 110 cN / 3 cm in Example 5, 54 cN / 3 cm in Example 6, 88 cN / 3 cm in Example 7, 92 cN / 3 cm in Example 8, 95 cN / 3 cm in Example 9, 95 cN / 3 cm in Example 10 Met. On the other hand, Comparative Example 1 was 150 cN / 3 cm, Comparative Example 2 was 99 cN / 3 cm, Comparative Example 3 was 101 cN / 3 cm, and Comparative Example 4 was 109 cN / 3 cm.
[0095]
When the load direction is BS, 82 cN / 3 cm in Example 1, 75 cN / 3 cm in Example 2, 83 cN / 3 cm in Example 3, 95 cN / 3 cm in Example 4, 108 cN / 3 cm in Example 5. Example 6 was 53 cN / 3 cm, Example 7 was 88 cN / 3 cm, Example 8 was 92 cN / 3 cm, Example 9 was 95 cN / 3 cm, and Example 10 was 97 cN / 3 cm. On the other hand, 117 cN / 3 cm in Comparative Example 1, 76 cN / 3 cm in Comparative Example 2, 85 cN / 3 cm in Comparative Example 3, and 96 cN / 3 cm in Comparative Example 4.
[0096]
Therefore, the three-point bending stiffness in the warp direction is 110 cN / 3 cm or less in the double weft texture, and 100 cN / 3 cm or less in the single weft texture, and the flexibility in the warp direction is good. It was confirmed.
[0097]
Furthermore, the dryer canvas of the present invention is a double weave texture with the same weft structure, and polyester monofilaments of the same material with the same dimension in the canvas thickness direction are used for the warp. When compared with a conventional dryer canvas having substantially the same or smaller warp filling rate, that is, Example 2 and Comparative Example 2, Example 1 and Comparative Example 3, or Example 3 and Example 4 and Comparative Example 4 was compared, it was found that the three-point bending rigidity in the warp direction was smaller in the example than in the comparative example, and the flexibility in the warp direction was extremely good.
[0098]
Next, the measurement results of the three-point bending stiffness in the weft direction are 935 cN / 3 cm in Example 1, 880 cN / 3 cm in Example 2, and 969 cN / 3 cm in Example 3, when the load direction is PS. 4 at 1,076 cN / 3 cm, Example 5 at 1,291 cN / 3 cm, Example 6 at 505 cN / 3 cm, Example 7 at 857 cN / 3 cm, Example 8 at 884 cN / 3 cm, Example 9 at 602 cN / 3 cm, In Example 10, it was 609 cN / 3 cm. On the other hand, it was 627 cN / 3 cm in Comparative Example 1, 662 cN / 3 cm in Comparative Example 2, 889 cN / 3 cm in Comparative Example 3, and 862 cN / 3 cm in Comparative Example 4.
[0099]
When the load direction is BS, 929 cN / 3 cm in Example 1, 881 cN / 3 cm in Example 2, 975 cN / 3 cm in Example 3, 1,074 cN / 3 cm in Example 4, 1 in Example 5 289 cN / 3 cm, Example 6 504 cN / 3 cm, Example 7 856 cN / 3 cm, Example 8 885 cN / 3 cm, Example 9 602 cN / 3 cm, and Example 10 609 cN / 3 cm. On the other hand, it was 665 cN / 3 cm in Comparative Example 1, 668 cN / 3 cm in Comparative Example 2, 931 cN / 3 cm in Comparative Example 3, and 903 cN / 3 cm in Comparative Example 4.
[0100]
Therefore, the three-point bending stiffness in the weft direction is 500 cN / 3 cm or more in the double weft texture, and 500 cN / 3 cm or more in the single weft texture, confirming that the stiffness in the weft direction is high. It was done.
[0101]
Furthermore, the dryer canvas of the present invention is a double weave texture with the same weft structure, and polyester monofilaments of the same material with the same dimension in the thickness direction of the canvas are used for the warp, and the air permeability is almost equal. When comparing the conventional dryer canvas having, that is, Example 2 and Comparative Example 2, Example 1 and Comparative Example 3, or Example 3 and Example 4 and Comparative Example 4 are compared, Example It was found that the three-point bending rigidity in the weft direction was larger than that of the comparative example, and the three-point bending rigidity in the weft direction was higher.
(Evaluation of running stability)
The deviation angles (θ1, θ2) before and after heating of the dryer canvases of Examples 1 to 10 and Comparative Examples 1 to 4 above were measured by the above-described deviation angle test method. Deviation was estimated, and form stability characteristics and running stability were evaluated.
[0102]
The measurement was performed with 3 samples for each canvas, and the measurement results are shown in Table 8.
[0103]
[Table 8]

[0104]
As a result, using the dryer canvas of the present invention, the polyester monofilament of the same material as the warp, and the cross-sectional circular polyester monofilament of the same material having a high dry heat shrinkage rate as the weft, weft double having substantially the same air permeability When comparing the conventional dryer canvas composed of the above-mentioned twill texture, that is, when comparing Example 7 and Example 8 with Comparative Example 2, the deviation angle (θ1) before heating is 1 in Example 7. .2 °, 1.1 ° in Example 8, 1.0 ° in Comparative Example 2, and the deviation angle (θ2) after heating is 2.5 ° in Example 7, 2.4 ° in Example 8, In Comparative Example 2, it was 2.6 °, and both the pre-heating and post-heating misalignment angles were almost the same as the comparative example.
[0105]
Also, the dryer canvas of the present invention is a double weave texture with the same weave structure, and the same thickness and the same material and polyester monofilaments of the same material as warp and the same cross-sectional shape When the cross-sectional circular polyester monofilament having a high dry heat shrinkage ratio of the material is used for the weft, when compared with a conventional dryer canvas having substantially the same air permeability, that is, when Example 4 and Comparative Example 4 are compared, The deviation angle (θ1) before heating is 1.0 ° in Example 4, 1.0 ° in Comparative Example 4, and the deviation angle (θ2) after heating is 2.4 ° in Example 4 and Comparative Example 4 It was 2.5 °, and both the pre-heating and post-heating misalignment angles were almost equal to or smaller than those of the comparative example.
[0106]
Therefore, the dryer canvas of the present invention has the same weaving structure, in particular, using a monofilament having a square cross section for warp, compared to the dryer canvas having a substantially same air permeability and having been used for a long time (Comparative Example 2). Compared with the dryer canvas (Comparative Example 4), which has almost the same air permeability and has been used for the wide- and high-speed paper machine dryers in the past, the displacement of the weave structure is almost the same. Thus, it was found to be excellent in form stability characteristics and running stability.
(Evaluation of surface smoothness in flow direction and width direction)
The static friction coefficient and the dynamic friction coefficient in the flow direction (warp direction) and the width direction (weft direction) of the dryer canvases of Examples 1 to 6 and Comparative Examples 1 to 4 were measured by the above test method, and the flow direction and width were measured. The surface smoothness in the direction was evaluated.
[0107]
The measurement was performed with 3 samples for each canvas, and the measurement results are shown in Table 9.
[0108]
[Table 9]

[0109]
As a result, the dryer canvas of the present invention is a double weave texture with the same weft structure, polyester monofilament warp of the same material with the same dimension in the canvas thickness direction, and the same material with the same cross-sectional shape The cross-sectional circular polyester monofilament wefts of the present invention were compared with a conventional dryer canvas having substantially the same air permeability, that is, Example 1 and Comparative Example 3, or Example 3 and Comparative Example 4 were compared. In this case, the static friction coefficient in the warp direction is 0.177 in Example 1, 0.170 in Example 3, 0.201 in Comparative Example 3, 0.200 in Comparative Example 4, and the dynamic friction coefficient in the warp direction is Example 1 is 0.257, Example 3 is 0.278, Comparative Example 3 is 0.290, Comparative Example 4 is 0.285, and the coefficient of static friction in the weft direction is 0.177 in Example 1. , Example 3 is 0.180, Comparative Example 3 is 0.207, Comparative Example 4 is 0.200, and the dynamic friction coefficient in the weft direction is 0.285 in Example 1, 0.248 in Example 3, and comparison. Example 3 was 0.319 and Comparative Example 4 was 0.311, and both the static friction coefficient and the dynamic friction coefficient in the canvas flow direction (warp direction) and the canvas width direction (weft direction) were compared with each other. The result was very good in comparison.
[0110]
Also, the dryer canvas of the present invention is a double weave texture with the same weft structure, the polyester monofilament warp of the same material with the same dimension in the canvas thickness direction, and the same material with the same cross-sectional shape. When a cross-sectional circular polyester monofilament weft having a high dry heat shrinkage is used and compared with a conventional dryer canvas having substantially the same air permeability, that is, Example 2 and Comparative Example 2, or Example 4 and Comparative Example 4. The static friction coefficient in the warp direction is 0.175 in Example 2, 0.165 in Example 4, 0.203 in Comparative Example 2, 0.200 in Comparative Example 4, and the dynamic friction coefficient in the warp direction. Is 0.282 in Example 2, 0.254 in Example 4, 0.294 in Comparative Example 2, 0.285 in Comparative Example 4, and the static friction coefficient in the weft direction is 0.176 in Example 2. Example 4 0.173, 0.214 in Comparative Example 2, 0.200 in Comparative Example 4, the dynamic friction coefficient in the weft direction is 0.268 in Example 2, 0.247 in Example 4, and 0.275 in Comparative Example 2. In Comparative Example 4, it was 0.311, and both the static friction coefficient and the dynamic friction coefficient in the flow direction of the canvas (warp direction) and the width direction of the canvas (weft direction) were very good compared to the comparative example. It was a result.
[0111]
Therefore, the dryer canvas of the present invention has a substantially equal air permeability, and is superior to conventional canvases having good surface smoothness (comparative example 3 and comparative example 4) in which the cross-sectionally square polyester monofilament is arranged on the warp. Compared with the conventional canvas (Comparative Example 2) suitable for applications that require a high grade of quality, with a high density of circular cross-sectional polyester monofilaments with a thin wire diameter on the warp, which has almost the same air permeability. It was confirmed that the canvas had excellent surface smoothness in both the flow direction and the width direction.
[0112]
【The invention's effect】
According to the present invention, in a dryer canvas for a paper machine made of a synthetic fiber fabric, the warp yarn is inscribed in a quadrangle having a thickness dimension smaller than the width dimension, and a continuous curve, or a thickness direction consisting of a straight line and a continuous curve. Using a monofilament having a cross-sectional shape without a straight part in the thickness direction and having a cross-sectional area larger than the area of a regular ellipse inscribed in the rectangle, 130 Because it was in the high range of% to 175% , Compared to conventional dryer canvases that have been used in applications that require a high level of quality, it has superior surface smoothness, for example, for applications that require a high level of quality, such as high-quality paper and base paper for coating. It is possible to realize a dryer canvas for a papermaking machine that can be suitably used.
[0113]
Furthermore, according to the present invention, it is possible to achieve a thickness that can be applied to a single-run canvas system or a drying section of a type in which cylinders are arranged in a single row, and at the same time, a wide width that can also be applied to a wide and high speed paper machine.・ Compared with conventional dryer canvas that has been used in high-speed paper machine dryers, it has extremely good flexibility in the warp direction and sufficient rigidity in the weft direction. For example, the canvas width dimension is 9m or more. It is possible to realize a dryer canvas for a papermaking machine having excellent shape retention characteristics and running stability including conditions of a papermaking speed of 1,500 m / min. Or more, and a wide air permeability adjustment range.
[0114]
In addition, by using the “cross-sectional shape having no straight portion in the thickness direction” monofilament for warp, the strength per warp exceeds at least 79% of the strength of the circumscribed square made of the same material and is 96% or less. Therefore, a monofilament having a cross-sectional shape of the circumscribed square was used for the warp by setting the warp filling rate corresponding to the cross-sectional area ratio with the circumscribed square within the range of the warp filling rate of 130% or more and 175% or less. It is possible to achieve warp direction strength equal to or higher than the case.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory view showing various forms of a canvas woven structure to which the present invention can be applied, expressed from warp direction cross sections;
(A) is a weaving structure of 2/2 regular obliques and 2/2 broken oblique wefts in which a large amount of warp appears on the surface of the paper contact surface side,
(B) is a 3/3 regular oblique, 3/3 broken oblique, 3/3 sudden oblique or 3/3 sudden broken oblique weft double weaving, where the warp on the paper contact side and the reverse paper surface side floats long. Woven tissue,
(C) is a woven structure of a 2/1 regular oblique line or a 2/1 broken oblique line weft where a large amount of warp is expressed on the surface of the paper contact surface side,
(D) is a woven structure of 3/1 regular or 3/1 broken oblique or 3/1 suddenly broken or 3/1 suddenly broken weft with a single warp. It is.
FIG. 2A is a cross-sectional view of a warp having an elliptical cross-sectional shape;
(B) is a cross-sectional view of an example of a warp having a cross-sectional shape according to the present invention,
(C) is a cross-sectional view of a different example of warp having a cross-sectional shape according to the present invention,
(D) is sectional drawing of the further another example of the warp which has the cross-sectional shape which concerns on this invention.
FIG. 3 is an explanatory diagram of a test method for a three-point bending rigidity of a dryer canvas.
FIG. 4A is an explanatory diagram of a method for measuring a deviation angle of a dryer canvas,
(B) is a perspective view at the time of load in the displacement angle measuring device of the dryer canvas,
(C) is a perspective view at the time of measuring a deviation angle in a deviation angle measuring device of a dryer canvas.
FIG. 5 is a schematic configuration diagram of a friction coefficient measuring device for a dryer canvas.
FIG. 6A is an explanatory view of an enlarged cross section of a main part on the paper contact surface side of a canvas using a warp having a square cross section in the prior art,
(B) is explanatory drawing of the principal part expanded cross section in the paper contact surface side of the canvas using the warp which has the cross-sectional shape of this invention.
FIG. 7 is a schematic explanatory view from a cross section in the warp direction of each woven structure used in Examples and Comparative Examples of the present invention,
(A) is a canvas weave structure having a weft double weave structure with a 2/2 tear on the paper contact side,
(B) is a canvas weave structure having a weft double weave structure in which the paper contact side is broken by 1/3.
FIG. 8 is a schematic explanatory view from a cross section in the warp direction of each woven structure used in the examples of the present invention,
(A) is a canvas weave structure of a weft 1 double weave structure with a 2/2 broken oblique where the warp on the paper contact side floats long,
(B) is a canvas weave structure having a weft single weave structure of a 3/1 broken oblique text in which the warp on the paper contact surface side floats long.
[Explanation of symbols]
10, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 300, 310, 320, 330 Dryer canvas
11, 101, 161, 181, 191 Warp
12,102,162,182,192 Weft
13 Paper contact side
14 Rectangling paper side
20 Mathematically defined regular oval shape
21, 22 A cross-sectional shape inscribed in a quadrilateral whose thickness dimension is smaller than the width dimension, and having a cross-sectional area larger than the area of a regular ellipse inscribed in the quadrangle,
23 A cross-section inscribed in a quadrangle whose thickness dimension is smaller than the width dimension, having no straight line portion in the thickness direction composed of a straight line and a continuous curve, and having a cross-sectional area larger than the area of a regular ellipse inscribed in the quadrangle shape
30 Friction coefficient measuring device
50 Deviation angle measuring device
70 warp
71 canvas surface
PS Paper contact side
BS Reverse paper side
X width dimension
Y thickness dimension
Z Length of straight section
m, k, l, n curves
p straight line

Claims (6)

A dryer canvas for a paper machine made of synthetic fiber fabric, in which warp yarns are inscribed in a square having a thickness dimension smaller than a width dimension, and a continuous curve, or a straight portion in a thickness direction consisting of a straight line and a continuous curve. A synthetic fiber monofilament having a cross-sectional area larger than the regular oval area inscribed in the square and having a warp filling ratio in a range of 130% to 175%. Dryer canvas for paper machines.   The synthetic fiber monofilament used for the warp is a cross section having no straight portion in the thickness direction inscribed in a square having a thickness dimension × width dimension of 0.25 mm to 0.40 mm × 0.35 mm to 0.80 mm. 2. A dryer canvas for a papermaking machine according to claim 1, wherein the dryer canvas has a shape.   The monofilament having a cross-sectional shape having no straight portion in the thickness direction used for the warp is inscribed and inscribed in a quadrangle within a ratio of thickness dimension: width dimension of 1: 1.25 to 1: 2. The dryer canvas for a papermaking machine according to claim 1 or 2, wherein the dryer canvas has a cross-sectional area in a range of more than 0.79 times and less than 0.96 times the cross-sectional area of the square. The dryer canvas for a papermaking machine according to any one of claims 1 to 3, wherein a monofilament having a high dry heat shrinkage rate is used for at least one layer of the weft.   Using a monofilament having a cross-section with a diameter in the range of 0.40 mm to 0.80 mm for at least the paper-contacting surface-side wefts and / or the counter-contacting surface-side wefts, and having a thickness The dryer canvas for a papermaking machine according to any one of claims 1 to 4, wherein the dimension is in a range of 1.30 mm to 1.80 mm.   It consists of a weft monoclinic weaving structure where warp yarns float at least on the surface of the paper-contacting surface. The weft yarn uses a circular monofilament with a cross-sectional diameter in the range of 0.60 mm to 1.00 mm. Is in the range of 1.00 mm to 1.60 mm, the dryer canvas for papermaking machine according to any one of claims 1 to 4.

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