【０００１】
【発明の属する技術分野】
本発明は、かつら、ヘアピース等の頭髪装飾や人形の頭髪に使用される人工毛髪用繊維に関する。
【０００２】
【従来の技術】
従来、頭髪装飾や人形の頭髪に使用される人工毛髪用繊維は、塩化ビニル系樹脂を溶媒を使用して紡糸する湿式紡糸方法、乾式紡糸方法等の方法で工業的に製造されている。
【０００３】
しかし、湿式紡糸方法は溶媒を使用するため脱溶媒工程を必要とし、巨大な設備と人が必要であるという欠点があり、乾式紡糸方法のほうが好ましいが、乾式紡糸方法では押出機を使用し、高温高圧で押出すため、押出時に熱分解したり、繊維が黄色に着色することがあった。
【０００４】
又、塩化ビニル系樹脂は人工毛髪用繊維としての外観、風合い等が優れ、着色性が優れているので人工毛髪用繊維として広く使用されているが、耐熱性や剛性が不足し、これを向上させるために塩素化塩化ビニル系樹脂を併用することが提案されている（例えば、特許文献１参照）。
【０００５】
しかし、塩素化塩化ビニル系樹脂を併用すると、押出成形性が低下し、押出成形条件がより高温高圧になるので、乾式紡糸の際に初期着色しやすくなる欠点あり、その改善のための手段が種々提案されている。
【０００６】
例えば、塩化ビニル系樹脂１００〜６０重量％と塩素化塩化ビニル系樹脂０〜４０重量％からなる塩化ビニル系樹脂１００重量部に対し、熱可塑性ポリウレタン樹脂２〜３５重量部と熱安定剤と滑剤を配合した樹脂組成物からなる塩化ビニル系繊維が提案されている（例えば、特許文献２参照）。
【０００７】
又、塩化ビニル系樹脂１００〜６０重量％と塩素化塩化ビニル系樹脂０〜４０重量％からなる塩化ビニル系樹脂１００重量部に対し、エチレン−酢酸ビニル系樹脂１〜３５重量部と熱安定剤と滑剤を配合した樹脂組成物からなる塩化ビニル系繊維が提案されている（例えば、特許文献３参照）。
【０００８】
しかし、上記塩化ビニル系繊維は、柔らかい熱可塑性ポリウレタン樹脂やエチレン−酢酸ビニル系樹脂を添加するため繊維の剛性、風合い等が低下し、又、初期着色性は改善されず依然として黄色味がかっており、鮮明な色彩を有する人工毛髪用繊維としては不充分な繊維であった。
【０００９】
【特許文献１】
特開昭５５−１３８８号公報
【特許文献２】
特開平１１−６１５５７号公報
【特許文献３】
特開平１１−１００７１４号公報
【００１０】
【発明が解決しようとする課題】
本発明の目的は、上記欠点に鑑み、初期着色性が優れ、鮮明な色彩を付与することができ、且つ人毛によく似た風合い、強度を有する人工毛髪用繊維を提供することにある。
【００１１】
【課題を解決するための手段】
本発明の人工毛髪用繊維は、塩化ビニル系樹脂６０〜９５重量％と塩素化塩化ビニル系樹脂４０〜５重量％よりなり、該塩素化塩化ビニル系樹脂が塩化ビニル系樹脂を光照射することなく、６０〜１４０℃で塩素化反応することにより得られた塩素化塩化ビニル系樹脂であることを特徴とする。
【００１２】
本発明で使用される塩化ビニル系樹脂は、塩化ビニル単独重合体若しくは塩化ビニル単量体を主体（５０重量％以上含む）とする、塩化ビニル単量体と重合可能なビニルモノマーとの共重合体である。
【００１３】
上記ビニルモノマーとしては、例えば、酢酸ビニル、プロピオン酸ビニル等のビニルエステル：（メタ）アクリル酸メチル、（メタ）アクリル酸エチル等の（メタ）アクリル酸エステル：エチレン、プロピレン等のオレフィン：（メタ）アクリル酸、無水マレイン酸、アクリロニトリル、スチレン、塩化ビニリデンなどがあげられる。
【００１４】
上記塩化ビニル系樹脂の粘度平均重合度は、小さくなると熱収縮率が大きくなり、カール保持性、艶性等が低下し、逆に大きくなると成形加工性が低下し、初期着色性の優れた繊維が得られなくなるので、６００〜２０００のものが好ましく、より好ましくは７００〜１４５０である。
【００１５】
本発明で使用される塩素化塩化ビニル系樹脂は、上記塩化ビニル系樹脂に光照射することなく、６０〜１４０℃で塩素化反応することにより得られた塩素化塩化ビニル系樹脂である。
【００１６】
上記塩素化に使用される塩化ビニル系樹脂は、前記の任意の塩化ビニル系樹脂が使用されうるが、粘度平均重合度は、小さくなると熱収縮率が大きくなり、カール保持性、艶性等が低下し、逆に大きくなると成形加工性が低下し、初期着色性の優れた繊維が得られなくなるので、４００〜１６００のものが好ましく、より好ましくは５００〜１２００である。
【００１７】
又、塩化ビニル系樹脂の平均粒子径は小さくなると取り扱いが困難になり、大きくなると塩素化反応時間が長くなるので、８０〜２００μｍが好ましい。
【００１８】
上記塩素化反応は、塩化ビニル系樹脂に光照射することなく、６０〜１４０℃で塩素化反応する以外は、従来公知の塩化ビニル系樹脂の塩素化方法が採用されてよい。
【００１９】
即ち、例えば、密閉可能な反応容器内に塩化ビニル系樹脂を水性媒体に懸濁させ、反応容器内を減圧した後、塩素を反応容器内に導入し、塩化ビニル系樹脂を塩素化する方法であって、塩素化の際に光照射せず、６０〜１４０℃に加熱して、熱により塩素化する。
【００２０】
上記反応容器内の減圧条件は、酸素が多量に存在すると、得られた塩素化塩化ビニル系樹脂の熱安定性が低下するので、反応容器内の酸素残存量が１００ｐｐｍ以下になるように減圧されるのが好ましい。
【００２１】
塩素は、反応容器内を減圧した後、反応容器内に導入されるが、塩素に酸素が多量に含まれていると得られた塩素化塩化ビニル系樹脂の熱安定性が低下するので、酸素含有量が１００ｐｐｍ以下の塩素を用いるのが好ましい。
【００２２】
塩素の導入量は、少なくなると塩素化反応が進みにくくなり、多くなると高価な反応容器が必要となり、コスト的に不利になるので、反応容器内の塩素分圧で０．１〜１．０ＭＰａが好ましく、より好ましくは０．２〜０．５ＭＰａである。尚、塩素分圧は、塩素化反応中一定であってもよいし、塩素化反応の進行につれて段階的に高くしてもよい。
【００２３】
上記加熱温度は、低くなると塩素化反応が遅くなり、高くなると反応中に脱塩酸反応がおこるようになり、得られた塩素化塩化ビニル系樹脂の熱安定性が低下するので、６０〜１４０℃であり、好ましくは７０〜１３０℃である。
【００２４】
又、塩素化反応を促進し、より熱安定性の優れた塩素化塩化ビニル系樹脂を得るために、塩素化反応中に過酸化水素が添加されるのが好ましい。
【００２５】
上記過酸化水素は純粋なものでもよいが、取り扱いしやすい水溶液が好適に使用される。過酸化水素の添加量は、少なくなると塩素化反応促進効果が得られず、多くなると得られた塩素化塩化ビニル系樹脂の熱安定性が低下するので、塩化ビニル系樹脂に対し４〜５０ｐｐｍ／ｈｒが好ましく、より好ましくは５〜３０ｐｐｍ／ｈｒである。
【００２６】
上記過酸化水素の添加方法は公知の任意の方法が採用されてよく、例えば、初期一括添加方法、間欠的添加方法、連続的添加方法等が挙げられる。又、添加時期も適宜決定されればよいが、塩化ビニル系樹脂の塩素含有量が６０重量％以上になった時点から添加すると、塩素化反応が安定して進み、熱安定性の優れた塩素化塩化ビニル系樹脂が得られるので好ましい。
【００２７】
又、得られた塩素化塩化ビニル系樹脂の塩素含有量は、少なくなると塩化ビニル系樹脂に近くなり、耐熱性、強度等が低下し、逆に多くなると成形加工性が低下し、初期着色性の優れた繊維が得られなくなるので、５８〜７２重量％が好ましく、より好ましくは６０〜７０重量％である。
【００２８】
上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂の添加比率は、塩素化塩化ビニル系樹脂の量が少なくなると、耐熱性、剛性等が低下し、多くなると成形加工性が低下し、初期着色性の優れた繊維が得られなくなるので、塩化ビニル系樹脂６０〜９５重量％と塩素化塩化ビニル系樹脂４０〜５重量％よりなり、好ましくは、塩化ビニル系樹脂７０〜９０重量％と塩素化塩化ビニル系樹脂３０〜１０重量％である。
【００２９】
本発明の人工毛髪用繊維は上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂よりなるが、必要に応じて、例えば、メチルメタクリレ−ト系樹脂、エチレン−酢酸ビニル系共重合体、熱可塑性ポリウレタン樹脂等の熱可塑性樹脂が添加されてもよい。
【００３０】
上記熱可塑性樹脂の添加量は、多くなると繊維が柔らかくなり、毛髪としての風合いが低下するので、上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂の合計１００重量部に対し２０重量部以下が好ましい。
【００３１】
又、人工毛髪用繊維の製造の際の熱安定性、成形性等の向上や得られた人工毛髪用繊維の光安定性の向上のために、従来より塩化ビニル系樹脂の成形の際に使用されている熱安定剤、滑剤、改質剤、加工助剤、酸化防止剤、帯電防止剤、難燃剤、光安定剤、無機充填剤、着色剤、可塑剤等が添加されてもよい。
【００３２】
上記熱安定剤としては、塩化ビニル系樹脂の熱安定剤として一般に使用されている任意の熱安定剤が使用でき、例えば、ステアリン酸カルシウム、ラウリン酸バリウムステアリン酸亜鉛などの金属石鹸系熱安定剤；ジメチル錫ジメルカプト、ジブチル錫ジメルカプト、ジオクチル錫ジメルカプト、ジメチル錫ジマレート、ジブチル錫ジマレート、ジオクチル錫ジマレート、ジメチル錫ジラウレート、ジブチル錫ジラウレート、ジオクチル錫ジラウレートなどの錫系熱安定剤；ハイドロタルサイト系熱安定剤、ゼオライト系熱安定剤等が挙げられる。
【００３３】
熱安定剤の添加量は、必要に応じて適宜決定されればよいが、一般に上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂の合計１００重量部に対し０．２〜５重量部が好ましい。
【００３４】
上記滑剤としては、塩化ビニル系樹脂の滑剤として一般に使用されている任意の滑剤が使用でき、例えば、ステアリン酸、パルミチン酸、ラウリン酸などの高級脂肪酸系滑剤、ペンタエリスリトール又はジペンタエリスリトールと高級脂肪酸とのエステルであるペンタエリスリトール系滑剤；ステアリルアルコール、ラウリルアルコール、オレイルアルコールなどの高級アルコール系滑剤；ステアリルアルコール、ラウリルアルコール、オレイルアルコールなどの高級アルコールとモンタン酸とのエステルであるモンタン酸ワックス系滑剤等が挙げられる。
【００３５】
滑剤の添加量は、必要に応じて適宜決定されればよいが、一般に上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂の合計１００重量部に対し０．２〜５重量部が好ましい。
【００３６】
上記改質剤としては、塩化ビニル系樹脂の改質剤として一般に使用されている任意の改質剤が使用でき、例えば、メチルメタクリレート−ブタジエン−スチレン共重合体（ＭＢＳ樹脂）等が挙げられる。
【００３７】
改質剤の添加量は、必要に応じて適宜決定されればよいが、一般に上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂の合計１００重量部に対し０．２〜１０重量部が好ましい。
【００３８】
上記加工助剤としては、塩化ビニル系樹脂の加工助剤として一般に使用されている任意の加工助剤が使用でき、例えば、メチルメタクリレートを主体とするアクリル系加工助剤、熱可塑性ポリエステルを主体とするポリエステル系加工助剤等が挙げられる。
【００３９】
加工助剤の添加量は、必要に応じて適宜決定されればよいが、一般に上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂の合計１００重量部に対し０．２〜１０重量部が好ましい。
【００４０】
上記無機充填剤としては、塩化ビニル系樹脂の無機充填剤として一般に使用されている任意の無機充填剤が使用でき、例えば、炭酸カルシウム、炭酸マグネシウム、酸化アルミニウム、酸化マグネシウム、酸化チタン、水酸化マグネシウム、タルク、マイカ、クレー等が挙げられる。
【００４１】
無機充填剤の添加量は、必要に応じて適宜決定されればよいが、一般に上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂の合計１００重量部に対し０．２〜５重量部が好ましい。
【００４２】
上記着色剤としては、塩化ビニル系樹脂の着色剤として一般に使用されている任意の着色剤が使用でき、例えば、アゾ系、フタロシアニン系、染料レーキ系などの有機顔料；酸化物系、水酸化物系、硫化物系、燐酸塩系、炭酸塩系無機顔料等が挙げられる。
【００４３】
着色剤の添加量は、必要に応じて適宜決定されればよいが、一般に上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂の合計１００重量部に対し０．０１〜１０重量部が好ましい。
【００４４】
上記可塑剤としては、塩化ビニル系樹脂の可塑剤として一般に使用されている任意の可塑剤が使用でき、例えば、ジオクチルフタレート、ジブチルフタレート、ジ−２エチルヘキシルフタレート、ジイソノニルフタレートなどのフタル酸系可塑剤；オクチルトリメリテートなどのトリメリット酸系可塑剤；オクチルピロメリテートなどのピロメリット酸系可塑剤、ポリエステル系可塑剤、エポキシ系可塑剤等が挙げられる。
【００４５】
可塑剤の添加量は、必要に応じて適宜決定されればよいが、一般に上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂の合計１００重量部に対し０．２〜２０重量部が好ましい。
【００４６】
人工毛髪用繊維の製造方法は従来公知の任意の製造方法が採用されてよく、例えば、上記塩化ビニル系樹脂と塩素化塩化ビニル系樹脂及び必要に応じ添加された熱安定剤、滑剤、加工助剤、酸化防止剤、帯電防止剤、難燃剤、光安定剤、無機充填剤、着色剤、可塑剤等からなる塩化ビニル系樹脂組成物を混合した後、又は混合しペレット化した後繊維状に押出成形する方法が挙げられる。
【００４７】
上記塩化ビニル系樹脂組成物の混合は、従来公知の混合機、例えば、ヘンシェルミキサー、スーパーミキサー、リボンブレンダー等で混合すればよく、この際に加熱し溶融混合してペレットコンパウンドとしてもよい。又、ペレット化は混合後、押出機、ニーダー、ロール等の混練機で混練することにより行われてもよい。
【００４８】
上記混合物又はペレットから繊維状に押出成形するには、単軸押出機、異方向二軸押出機、コニカル二軸押出機等の押出機で押出成形すればよい。押出温度は、低くなると押出できず、高温になりすぎると繊維が着色するようになるので、１５０〜１９０℃が好ましい。
【００４９】
又、得られた未延伸繊維に機械的強度、剛性、毛髪としての風合等を向上させるために２〜５倍程度延伸するのが好ましく、更に、延伸された繊維の熱収縮率を低下させるために熱処理を施して、２〜７５％程度の緩和率で熱緩和してもよい。
【００５０】
【発明の実施の形態】
次に本発明の実施例を説明する。
【００５１】
（実施例１）
３００リットルの攪拌装置付きグラスライニング製反応容器に、イオン交換水２００重量部と、粘度平均重合度８００の塩化ビニル樹脂５０重量部を供給し、攪拌して塩化ビニル樹脂をイオン交換水に懸濁しながら、反応容器内の酸素濃度が１０ｐｐｍになるまで空気を取り除いた後、反応容器内を１００℃に昇温した。
【００５２】
次いで、塩素（酸素濃度１０ｐｐｍ）を反応容器に導入し、塩素分圧が０．４ＭＰａになるように保持して５時間塩素化反応を行った。塩素化反応終了後、洗浄して、塩素含有率６６．５重量％の塩素化塩化ビニル樹脂を得た。尚、塩素化反応中、紫外線照射は行わなかった。
【００５３】
得られた塩素化塩化ビニル樹脂２０重量部、塩化ビニル樹脂（徳山積水社製、商品名ＴＳ−１０００Ｒ、粘度平均重合度１０００）８０重量部、アクリル系加工助剤（三菱レーヨン社製、商品名メタブレンＰ−７００）０．２重量部、ジオクチル錫ジメルカプト２重量部、ステアリン酸ブチル０．８重量部及びＭＢＳ樹脂（鐘淵化学社製、商品名カネエースＢ−５６）３重量部をヘンシェルミキサーに供給し、１００℃でコンパウディングし、口径４０ｍｍの単軸押出機で１６５℃で押出して、直径２ｍｍ未延伸繊維を得た。
【００５４】
得られた繊維を５倍に延伸し、直径０．４ｍｍの人工毛髪用繊維を得た。得られた人工毛髪用繊維の初期着色性を測定し風合いを目視で観察し結果を表１に示した。尚、測定方法は下記の通りである。
【００５５】
（１）初期着色性 ＪＩＳ Ｋ７１０５に準拠し、色差計（日本電色工業社製、ＮＲ−３０００）を用いて黄色度を測定した。
（２）風合い 目視で光沢を観察し、最も艶のあるものを◎で表示し、艶がなくなるにしたがって○、 △で表示し、最も艶のないものを×で表示した。
【００５６】
（実施例２）
粘度平均重合度８００の塩化ビニル樹脂を用い、反応容器内を６０℃にし、塩素の導入開始から過酸化水素水（濃度１重量％）を２０ｐｐｍ／ｈｒになるように供給した以外は実施例１で行ったと同様にして、塩素含有率６８．５重量％の塩素化塩化ビニル樹脂を得た。
【００５７】
得られた塩素化塩化ビニル樹脂５重量部と塩化ビニル樹脂（徳山積水社製、商品名ＴＳ−１０００Ｒ、粘度平均重合度１０００）９５重量部を使用した以外は、実施例１で行ったと同様にして、人工毛髪用繊維を得、実施例１で行ったと同様にして初期着色性を測定し風合いを目視で観察し結果を表１に示した。
【００５８】
（実施例３）
粘度平均重合度８００の塩化ビニル樹脂を用い、反応容器内を１４０℃にした以外は実施例１で行ったと同様にして、塩素含有率６４．０重量％の塩素化塩化ビニル樹脂を得た。
【００５９】
得られた塩素化塩化ビニル樹脂５重量部と塩化ビニル樹脂（徳山積水社製、商品名ＴＳ−１０００Ｒ、粘度平均重合度１０００）９５重量部を使用した以外は、実施例１で行ったと同様にして、人工毛髪用繊維を得、実施例１で行ったと同様にして初期着色性を測定し風合いを目視で観察し結果を表１に示した。
【００６０】
（実施例４）
粘度平均重合度８００の塩化ビニル樹脂を用い、反応容器内を１００℃にし、塩素の導入開始から過酸化水素水（濃度１重量％）を２０ｐｐｍ／ｈｒになるように供給した以外は実施例１で行ったと同様にして、塩素含有率６６．５重量％の塩素化塩化ビニル樹脂を得た。
【００６１】
得られた塩素化塩化ビニル樹脂３０重量部と塩化ビニル樹脂（徳山積水社製、商品名ＴＳ−１０００Ｒ、粘度平均重合度１０００）７０重量部を使用した以外は、実施例１で行ったと同様にして、人工毛髪用繊維を得、実施例１で行ったと同様にして初期着色性を測定し風合いを目視で観察し結果を表１に示した。
【００６２】
（比較例１）
３００リットルの紫外線照射装置及び攪拌装置付きグラスライニング製反応容器に、イオン交換水２００重量部と、粘度平均重合度８００の塩化ビニル樹脂５０重量部を供給し、攪拌して塩化ビニル樹脂をイオン交換水に懸濁しながら反応容器内の酸素濃度が１０ｐｐｍになるまで空気を取り除いた後、反応容器内を８０℃に昇温した。
【００６３】
次いで、紫外線を照射しながら、塩素（酸素濃度１０ｐｐｍ）を反応容器に導入し、塩素分圧が０．４ＭＰａになるように保持して８時間塩素化反応を行った。塩素化反応終了後、洗浄して、塩素含有率６６．５重量％の塩素化塩化ビニル樹脂を得た。
【００６４】
得られた塩素化塩化ビニル樹脂２０重量部と塩化ビニル樹脂（徳山積水社製、商品名ＴＳ−１０００Ｒ、粘度平均重合度１０００）８０重量部を使用した以外は、実施例１で行ったと同様にして、人工毛髪用繊維を得、実施例１で行ったと同様にして初期着色性を測定し風合いを目視で観察し結果を表１に示した。
【００６５】
（比較例２）
粘度平均重合度８００の塩化ビニル樹脂を用い、反応容器内を１００℃にし、実施例１で行ったと同様にして、塩素含有率６６．５重量％の塩素化塩化ビニル樹脂を得た。
【００６６】
得られた塩素化塩化ビニル樹脂５０重量部と塩化ビニル樹脂（徳山積水社製、商品名ＴＳ−１０００Ｒ、粘度平均重合度１０００）５０重量部を使用した以外は、実施例１で行ったと同様にして、人工毛髪用繊維を得、実施例１で行ったと同様にして初期着色性を測定し風合いを目視で観察し結果を表１に示した。
【００６７】
（比較例３）
粘度平均重合度８００の塩化ビニル樹脂を用い、反応容器内を５０℃にした以外は、実施例１で行ったと同様にして、塩素含有率６６．５重量％の塩素化塩化ビニル樹脂を得た。
【００６８】
得られた塩素化塩化ビニル樹脂２０重量部と塩化ビニル樹脂（徳山積水社製、商品名ＴＳ−１０００Ｒ、粘度平均重合度１０００）８０重量部を使用した以外は、実施例１で行ったと同様にして、人工毛髪用繊維を得、実施例１で行ったと同様にして初期着色性を測定し風合いを目視で観察し結果を表１に示した。
【００６９】
【表１】
【００７０】
【発明の効果】
本発明の人工毛髪用繊維の構成は上述の通りであるから初期着色性が優れ、鮮明な色彩を付与することができ、且つ、人毛によく似た風合いを有しており、かつら等に好適に使用できる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to artificial hair fibers used for hair decorations such as wigs, hairpieces, and the hair of dolls.
[0002]
[Prior art]
BACKGROUND ART Conventionally, artificial hair fibers used for hair decoration and doll's hair are industrially manufactured by a method such as a wet spinning method and a dry spinning method in which a vinyl chloride resin is spun using a solvent.
[0003]
However, the wet spinning method requires a desolvation step because of the use of a solvent, and has the disadvantage of requiring huge equipment and people, and the dry spinning method is more preferable, but the dry spinning method uses an extruder. Extrusion at high temperature and high pressure sometimes causes thermal decomposition during the extrusion and yellow coloration of the fiber.
[0004]
In addition, vinyl chloride resins are widely used as artificial hair fibers because of their excellent appearance, texture, etc. as artificial hair fibers, and excellent coloring properties. It has been proposed to use a chlorinated vinyl chloride-based resin in combination for the purpose (see, for example, Patent Document 1).
[0005]
However, when a chlorinated vinyl chloride resin is used in combination, the extrudability deteriorates, and the extrusion molding conditions become higher in temperature and pressure. Therefore, there is a disadvantage that initial coloring is easily performed during dry spinning. Various proposals have been made.
[0006]
For example, with respect to 100 parts by weight of a vinyl chloride resin comprising 100 to 60% by weight of a vinyl chloride resin and 0 to 40% by weight of a chlorinated vinyl chloride resin, 2 to 35 parts by weight of a thermoplastic polyurethane resin, a heat stabilizer and a lubricant Has been proposed (for example, see Patent Document 2).
[0007]
Also, with respect to 100 parts by weight of a vinyl chloride resin comprising 100 to 60% by weight of a vinyl chloride resin and 0 to 40% by weight of a chlorinated vinyl chloride resin, 1 to 35 parts by weight of an ethylene-vinyl acetate resin and a heat stabilizer And vinyl chloride-based fibers comprising a resin composition in which a lubricant is blended (for example, see Patent Document 3).
[0008]
However, the above-mentioned vinyl chloride fiber has a reduced rigidity and texture due to the addition of a soft thermoplastic polyurethane resin or an ethylene-vinyl acetate resin, and the initial colorability is not improved and is still yellowish. These fibers were insufficient as fibers for artificial hair having a vivid color.
[0009]
[Patent Document 1]
JP-A-55-1388 [Patent Document 2]
JP-A-11-61557 [Patent Document 3]
JP-A-11-100714
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION An object of the present invention is to provide an artificial hair fiber which has excellent initial coloring properties, can impart a vivid color, and has a texture and strength very similar to human hair, in view of the above-mentioned drawbacks.
[0011]
[Means for Solving the Problems]
The artificial hair fiber of the present invention comprises 60 to 95% by weight of a vinyl chloride resin and 40 to 5% by weight of a chlorinated vinyl chloride resin, and the chlorinated vinyl chloride resin irradiates the vinyl chloride resin with light. And a chlorinated vinyl chloride resin obtained by a chlorination reaction at 60 to 140 ° C.
[0012]
The vinyl chloride resin used in the present invention is mainly composed of a vinyl chloride homopolymer or a vinyl chloride monomer (containing at least 50% by weight), and is a copolymer of a vinyl chloride monomer and a polymerizable vinyl monomer. It is united.
[0013]
Examples of the vinyl monomer include vinyl esters such as vinyl acetate and vinyl propionate: (meth) acrylates such as methyl (meth) acrylate and ethyl (meth) acrylate: olefins such as ethylene and propylene: (meth) ) Acrylic acid, maleic anhydride, acrylonitrile, styrene, vinylidene chloride and the like.
[0014]
When the viscosity average polymerization degree of the vinyl chloride resin is small, the heat shrinkage is large, curl retention, glossiness, etc. are reduced, and conversely, when the viscosity average polymerization degree is large, molding processability is reduced, and fibers having excellent initial coloring properties are excellent. Is not preferably obtained, so that the number is preferably from 600 to 2,000, more preferably from 700 to 1450.
[0015]
The chlorinated vinyl chloride resin used in the present invention is a chlorinated vinyl chloride resin obtained by performing a chlorination reaction at 60 to 140 ° C. without irradiating the vinyl chloride resin with light.
[0016]
As the vinyl chloride resin used for the chlorination, any of the above-mentioned vinyl chloride resins can be used.However, the viscosity average degree of polymerization decreases, the heat shrinkage increases, the curl retention, gloss, etc. When it is decreased, and conversely, when it is increased, the molding processability is reduced and it becomes impossible to obtain a fiber having excellent initial coloring properties. Therefore, those having 400 to 1600 are preferable, and those having 500 to 1200 are more preferable.
[0017]
When the average particle size of the vinyl chloride resin is small, handling becomes difficult, and when the average particle size is large, the chlorination reaction time becomes long.
[0018]
In the chlorination reaction, a conventionally known chlorination method for a vinyl chloride resin may be employed, except that the chlorination reaction is performed at 60 to 140 ° C. without irradiating the vinyl chloride resin with light.
[0019]
That is, for example, a method in which a vinyl chloride resin is suspended in an aqueous medium in a hermetically sealable reaction vessel, and the pressure in the reaction vessel is reduced, then chlorine is introduced into the reaction vessel, and the vinyl chloride resin is chlorinated. Therefore, it is heated to 60 to 140 ° C. without irradiating light during chlorination, and chlorinated by heat.
[0020]
The reduced pressure condition in the reaction vessel is such that when a large amount of oxygen is present, the thermal stability of the obtained chlorinated vinyl chloride resin is reduced, so that the pressure is reduced so that the residual amount of oxygen in the reaction vessel becomes 100 ppm or less. Preferably.
[0021]
Chlorine is introduced into the reaction vessel after depressurizing the inside of the reaction vessel.However, if the chlorine contains a large amount of oxygen, the thermal stability of the obtained chlorinated vinyl chloride resin is reduced. It is preferable to use chlorine having a content of 100 ppm or less.
[0022]
When the introduction amount of chlorine is small, the chlorination reaction is difficult to proceed, and when the amount is large, an expensive reaction vessel is required, which is disadvantageous in terms of cost, so that the partial pressure of chlorine in the reaction vessel is 0.1 to 1.0 MPa. Preferably, it is more preferably 0.2 to 0.5 MPa. The chlorine partial pressure may be constant during the chlorination reaction or may be increased stepwise as the chlorination reaction proceeds.
[0023]
When the heating temperature is lower, the chlorination reaction is slower, and when the heating temperature is higher, a dehydrochlorination reaction occurs during the reaction, and the thermal stability of the obtained chlorinated vinyl chloride resin is reduced. And preferably 70 to 130 ° C.
[0024]
Further, in order to accelerate the chlorination reaction and obtain a chlorinated vinyl chloride resin having more excellent thermal stability, it is preferable to add hydrogen peroxide during the chlorination reaction.
[0025]
The hydrogen peroxide may be pure, but an aqueous solution that is easy to handle is preferably used. If the amount of added hydrogen peroxide is too small, the effect of accelerating the chlorination reaction cannot be obtained, and if it is too large, the thermal stability of the obtained chlorinated vinyl chloride resin decreases. hr is preferable, and more preferably 5 to 30 ppm / hr.
[0026]
As the method for adding hydrogen peroxide, any known method may be employed, and examples thereof include an initial batch addition method, an intermittent addition method, and a continuous addition method. The timing of addition may be determined as appropriate. However, when the chlorine content of the vinyl chloride-based resin is 60% by weight or more, the chlorination reaction proceeds stably, and chlorine having excellent heat stability is obtained. It is preferable because a vinyl chloride resin can be obtained.
[0027]
Also, the chlorine content of the obtained chlorinated vinyl chloride-based resin becomes lower and closer to that of the vinyl chloride-based resin, and the heat resistance, strength, etc., decrease. Since it becomes impossible to obtain an excellent fiber of the above, the content is preferably 58 to 72% by weight, more preferably 60 to 70% by weight.
[0028]
With respect to the addition ratio of the vinyl chloride resin and the chlorinated vinyl chloride resin, when the amount of the chlorinated vinyl chloride resin is small, heat resistance, rigidity, etc. are reduced, and when the amount is large, the moldability is reduced, and the initial coloring property is reduced. Therefore, it is difficult to obtain a fiber excellent in the chlorinated chloride content. Therefore, it is composed of 60 to 95% by weight of the vinyl chloride resin and 40 to 5% by weight of the chlorinated vinyl chloride resin, preferably 70 to 90% by weight of the vinyl chloride resin. It is 30 to 10% by weight of the vinyl resin.
[0029]
The artificial hair fiber of the present invention comprises the above-mentioned vinyl chloride resin and chlorinated vinyl chloride resin. If necessary, for example, methyl methacrylate resin, ethylene-vinyl acetate copolymer, thermoplastic resin A thermoplastic resin such as a polyurethane resin may be added.
[0030]
The amount of the thermoplastic resin to be added is preferably 20 parts by weight or less with respect to 100 parts by weight of the total of the vinyl chloride resin and the chlorinated vinyl chloride resin, because if the amount increases, the fibers become soft and the texture as hair decreases. .
[0031]
In addition, in order to improve the thermal stability and the moldability in the production of artificial hair fibers, and to improve the light stability of the obtained artificial hair fibers, it has been conventionally used in molding vinyl chloride resin. Heat stabilizers, lubricants, modifiers, processing aids, antioxidants, antistatic agents, flame retardants, light stabilizers, inorganic fillers, coloring agents, plasticizers, and the like may be added.
[0032]
As the heat stabilizer, any heat stabilizer generally used as a heat stabilizer for a vinyl chloride resin can be used. For example, metal soap heat stabilizers such as calcium stearate and barium zinc laurate; Tin-based heat stabilizers such as dimethyltin dimercapto, dibutyltin dimercapto, dioctyltin dimercapto, dimethyltin dimaleate, dibutyltin dimaleate, dioctyltin dimaleate, dimethyltin dilaurate, dibutyltin dilaurate, dioctyltin dilaurate; hydrotalcite-based heat stabilizers And a zeolite-based heat stabilizer.
[0033]
The amount of the heat stabilizer to be added may be appropriately determined as necessary, but is generally preferably 0.2 to 5 parts by weight based on 100 parts by weight of the total of the vinyl chloride resin and the chlorinated vinyl chloride resin.
[0034]
As the above lubricant, any lubricant generally used as a lubricant for vinyl chloride resin can be used, for example, higher fatty acid lubricants such as stearic acid, palmitic acid, lauric acid, pentaerythritol or dipentaerythritol and higher fatty acid Pentaerythritol-based lubricants which are esters with styrene; higher alcohol-based lubricants such as stearyl alcohol, lauryl alcohol and oleyl alcohol; montanic acid-based lubricants which are esters of higher alcohols such as stearyl alcohol, lauryl alcohol and oleyl alcohol with montanic acid And the like.
[0035]
The amount of the lubricant to be added may be appropriately determined as needed, but is generally preferably 0.2 to 5 parts by weight based on 100 parts by weight of the total of the vinyl chloride resin and the chlorinated vinyl chloride resin.
[0036]
As the modifier, any modifier generally used as a modifier for a vinyl chloride resin can be used, and examples thereof include a methyl methacrylate-butadiene-styrene copolymer (MBS resin).
[0037]
The amount of the modifier added may be appropriately determined as necessary, but is generally preferably 0.2 to 10 parts by weight based on 100 parts by weight of the total of the vinyl chloride resin and the chlorinated vinyl chloride resin.
[0038]
As the processing aid, any processing aid generally used as a processing aid for a vinyl chloride resin can be used, for example, an acrylic processing aid mainly composed of methyl methacrylate, mainly composed of a thermoplastic polyester. And other polyester-based processing aids.
[0039]
The amount of the processing aid to be added may be appropriately determined as necessary, but is generally preferably 0.2 to 10 parts by weight based on 100 parts by weight of the total of the vinyl chloride resin and the chlorinated vinyl chloride resin.
[0040]
As the inorganic filler, any inorganic filler generally used as an inorganic filler of a vinyl chloride resin can be used, for example, calcium carbonate, magnesium carbonate, aluminum oxide, magnesium oxide, titanium oxide, magnesium hydroxide , Talc, mica, clay and the like.
[0041]
The amount of the inorganic filler to be added may be appropriately determined as necessary, but is generally preferably 0.2 to 5 parts by weight based on 100 parts by weight of the total of the vinyl chloride resin and the chlorinated vinyl chloride resin.
[0042]
As the colorant, any colorant generally used as a colorant for a vinyl chloride resin can be used. For example, azo, phthalocyanine, dye lake-based organic pigments; oxides, hydroxides , Sulfide, phosphate and carbonate inorganic pigments.
[0043]
The amount of the colorant to be added may be appropriately determined as necessary, but is generally preferably 0.01 to 10 parts by weight based on 100 parts by weight of the total of the vinyl chloride resin and the chlorinated vinyl chloride resin.
[0044]
As the plasticizer, any plasticizer that is generally used as a plasticizer for a vinyl chloride resin can be used. A trimellitic acid-based plasticizer such as octyl trimellitate; a pyromellitic acid-based plasticizer such as octyl pyromellitate; a polyester-based plasticizer; and an epoxy-based plasticizer.
[0045]
The amount of the plasticizer to be added may be appropriately determined as necessary, but is generally preferably 0.2 to 20 parts by weight based on 100 parts by weight of the total of the vinyl chloride resin and the chlorinated vinyl chloride resin.
[0046]
As a method for producing the artificial hair fiber, any conventionally known production method may be adopted. For example, the above-mentioned vinyl chloride resin and chlorinated vinyl chloride resin, and a heat stabilizer, a lubricant, After mixing the vinyl chloride resin composition consisting of an agent, an antioxidant, an antistatic agent, a flame retardant, a light stabilizer, an inorganic filler, a colorant, a plasticizer, etc., or after mixing and pelletizing into a fibrous form Extrusion molding may be used.
[0047]
The above-mentioned vinyl chloride-based resin composition may be mixed by a conventionally known mixer, for example, a Henschel mixer, a super mixer, a ribbon blender, or the like. In this case, the mixture may be heated and melt-mixed to form a pellet compound. Further, pelletization may be performed by kneading with a kneading machine such as an extruder, a kneader or a roll after mixing.
[0048]
In order to extrude the mixture or pellet into a fibrous form, it may be extruded with an extruder such as a single screw extruder, a bidirectional twin screw extruder, or a conical twin screw extruder. The extrusion temperature is preferably from 150 to 190 ° C., since the extrusion cannot be performed when the temperature is low, and the fiber is colored when the temperature is too high.
[0049]
Further, it is preferable that the obtained unstretched fiber is stretched about 2 to 5 times in order to improve mechanical strength, rigidity, feeling as hair, etc., and further, the heat shrinkage of the stretched fiber is reduced. For this purpose, a heat treatment may be applied to thermally relax at a relaxation rate of about 2 to 75%.
[0050]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, examples of the present invention will be described.
[0051]
(Example 1)
200 parts by weight of ion-exchanged water and 50 parts by weight of a vinyl chloride resin having a viscosity average degree of polymerization of 800 are supplied to a 300-liter glass-lined reaction vessel equipped with a stirrer, and the vinyl chloride resin is suspended in the ion-exchanged water with stirring. While removing the air until the oxygen concentration in the reaction vessel became 10 ppm, the temperature inside the reaction vessel was raised to 100 ° C.
[0052]
Next, chlorine (oxygen concentration: 10 ppm) was introduced into the reaction vessel, and the chlorination reaction was performed for 5 hours while maintaining the chlorine partial pressure at 0.4 MPa. After completion of the chlorination reaction, washing was performed to obtain a chlorinated vinyl chloride resin having a chlorine content of 66.5% by weight. During the chlorination reaction, no ultraviolet irradiation was performed.
[0053]
20 parts by weight of the obtained chlorinated vinyl chloride resin, 80 parts by weight of a vinyl chloride resin (trade name: TS-1000R, manufactured by Tokuyama Sekisui Co., Ltd., viscosity average polymerization degree: 1000), acrylic processing aid (manufactured by Mitsubishi Rayon Co., trade name) 0.2 parts by weight of METABLEN P-700), 2 parts by weight of dioctyltin dimercapto, 0.8 parts by weight of butyl stearate, and 3 parts by weight of MBS resin (manufactured by Kaneka Chemical Co., Ltd., trade name: Kaneace B-56) in a Henschel mixer. The mixture was fed at 100 ° C., compounded at 100 ° C., and extruded at 165 ° C. by a single screw extruder having a diameter of 40 mm to obtain an undrawn fiber of 2 mm in diameter.
[0054]
The obtained fiber was stretched 5 times to obtain a fiber for artificial hair having a diameter of 0.4 mm. The initial coloring properties of the obtained artificial hair fibers were measured, and the texture was visually observed. The results are shown in Table 1. In addition, the measuring method is as follows.
[0055]
(1) Initial Colorability According to JIS K7105, the yellowness was measured using a color difference meter (NR-3000, manufactured by Nippon Denshoku Industries Co., Ltd.).
(2) Texture The gloss was visually observed, the most glossy ones were indicated by ◎, the less glossy ones were indicated by 、 and Δ, and the least glossy ones were indicated by x.
[0056]
(Example 2)
Example 1 Example 1 was repeated except that a vinyl chloride resin having a viscosity average degree of polymerization of 800 was used, the inside of the reaction vessel was kept at 60 ° C., and hydrogen peroxide solution (concentration: 1% by weight) was supplied at a concentration of 20 ppm / hr from the start of introduction of chlorine. In the same manner as described above, a chlorinated vinyl chloride resin having a chlorine content of 68.5% by weight was obtained.
[0057]
Except for using 5 parts by weight of the obtained chlorinated vinyl chloride resin and 95 parts by weight of a vinyl chloride resin (trade name: TS-1000R, manufactured by Tokuyama Sekisui Co., Ltd., viscosity average degree of polymerization: 1000), the same procedure as in Example 1 was used. Thus, an artificial hair fiber was obtained, the initial coloring property was measured in the same manner as in Example 1, the texture was visually observed, and the results are shown in Table 1.
[0058]
(Example 3)
A chlorinated vinyl chloride resin having a chlorine content of 64.0% by weight was obtained in the same manner as in Example 1 except that a vinyl chloride resin having a viscosity average degree of polymerization of 800 was used and the inside of the reaction vessel was kept at 140 ° C.
[0059]
Except for using 5 parts by weight of the obtained chlorinated vinyl chloride resin and 95 parts by weight of a vinyl chloride resin (trade name: TS-1000R, manufactured by Tokuyama Sekisui Co., Ltd., viscosity average degree of polymerization: 1000), the same procedure as in Example 1 was used. Thus, an artificial hair fiber was obtained, the initial coloring property was measured in the same manner as in Example 1, the texture was visually observed, and the results are shown in Table 1.
[0060]
(Example 4)
Example 1 Example 1 was repeated except that a vinyl chloride resin having a viscosity average degree of polymerization of 800 was used, the inside of the reaction vessel was set to 100 ° C., and hydrogen peroxide solution (concentration: 1% by weight) was supplied at 20 ppm / hr from the start of introduction of chlorine. In the same manner as described above, a chlorinated vinyl chloride resin having a chlorine content of 66.5% by weight was obtained.
[0061]
Except that 30 parts by weight of the obtained chlorinated vinyl chloride resin and 70 parts by weight of a vinyl chloride resin (trade name: TS-1000R, manufactured by Tokuyama Sekisui Co., Ltd., viscosity average degree of polymerization: 1000) were used in the same manner as in Example 1. Thus, an artificial hair fiber was obtained, the initial coloring property was measured in the same manner as in Example 1, the texture was visually observed, and the results are shown in Table 1.
[0062]
(Comparative Example 1)
200 parts by weight of ion-exchanged water and 50 parts by weight of vinyl chloride resin having a viscosity-average degree of polymerization of 800 are supplied to a 300-liter glass-lined reaction vessel equipped with an ultraviolet irradiation device and a stirrer, followed by stirring to ion-exchange the vinyl chloride resin. After suspending in water and removing air until the oxygen concentration in the reaction vessel became 10 ppm, the temperature in the reaction vessel was raised to 80 ° C.
[0063]
Next, while irradiating ultraviolet rays, chlorine (oxygen concentration: 10 ppm) was introduced into the reaction vessel, and a chlorination reaction was performed for 8 hours while maintaining the partial pressure of chlorine at 0.4 MPa. After completion of the chlorination reaction, washing was performed to obtain a chlorinated vinyl chloride resin having a chlorine content of 66.5% by weight.
[0064]
Except that 20 parts by weight of the obtained chlorinated vinyl chloride resin and 80 parts by weight of the vinyl chloride resin (trade name: TS-1000R, manufactured by Tokuyama Sekisui Co., Ltd., viscosity average polymerization degree: 1000) were used, the same as in Example 1 was used. Thus, an artificial hair fiber was obtained, the initial coloring property was measured in the same manner as in Example 1, the texture was visually observed, and the results are shown in Table 1.
[0065]
(Comparative Example 2)
A chlorinated vinyl chloride resin having a chlorine content of 66.5% by weight was obtained in the same manner as in Example 1 by using a vinyl chloride resin having a viscosity average degree of polymerization of 800 and keeping the inside of the reaction vessel at 100 ° C.
[0066]
Except for using 50 parts by weight of the obtained chlorinated vinyl chloride resin and 50 parts by weight of a vinyl chloride resin (trade name: TS-1000R, manufactured by Tokuyama Sekisui Co., Ltd., viscosity average degree of polymerization: 1000), the same procedure as in Example 1 was used. Thus, an artificial hair fiber was obtained, the initial coloring property was measured in the same manner as in Example 1, the texture was visually observed, and the results are shown in Table 1.
[0067]
(Comparative Example 3)
A chlorinated vinyl chloride resin having a chlorine content of 66.5% by weight was obtained in the same manner as in Example 1 except that a vinyl chloride resin having a viscosity average degree of polymerization of 800 was used and the inside of the reaction vessel was heated to 50 ° C. .
[0068]
Except that 20 parts by weight of the obtained chlorinated vinyl chloride resin and 80 parts by weight of the vinyl chloride resin (trade name: TS-1000R, manufactured by Tokuyama Sekisui Co., Ltd., viscosity average polymerization degree: 1000) were used, the same as in Example 1 was used. Thus, an artificial hair fiber was obtained, the initial coloring property was measured in the same manner as in Example 1, the texture was visually observed, and the results are shown in Table 1.
[0069]
[Table 1]
【The invention's effect】
Since the configuration of the artificial hair fiber of the present invention is as described above, the initial coloring property is excellent, a clear color can be imparted, and the texture is very similar to human hair. It can be suitably used.