JP3792984B2 - Antibacterial and antifungal processing methods for fibers - Google Patents

Description

【００１５】
ピリチオン亜鉛は亜鉛が人体の必須成分であり、安全性が高いこと、この亜鉛（Ｚｎ）の入った化合物は皮膚から吸収されにくいこと等の特徴がある。
【００１６】
これらの特性を備えていることからピリチオン亜鉛は、化粧品や洗髪剤の分野において広く使用されている実績がある。
ピリチオン亜鉛は通常粉末状を呈するが、そのままでは、繊維類を抗菌・抗カビ加工用としては用い得ない。
即ち、繊維にピリチオン亜鉛を強力な耐洗濯性を備えた状態で、担持させるためにはピリチオン亜鉛を特殊な状態にする必要が生じる。
【００１７】
第１の大きな要件は、分散液のｐＨである、ピリチオン亜鉛の分散液又はこの分散液を希釈した繊維加工用分散液（以下「加工液」という場合がある）が所定の範囲からアルカリ性側や酸性側にずれると、ピリチオン亜鉛の分解が進み、所望の効力が得られなくなり易いし、経時的に安定な分散液（加工液も含む）とならない。
【００１８】
安定状態を長期に渡って保ち、繊維に対するピリチオン亜鉛の固定率を向上させるため、分散液（「加工液も含む」以下同様）は、粉砕中又は粉砕後にｐＨを４〜１０の間、好ましくは５．５〜８．５、より好ましくは６〜８の間に調整される事が望ましい。
ｐＨの調整は、分散液のｐＨがアルカリ性側にある場合は、酢酸、塩酸、リン酸等の酸を所定量添加し、上記のｐＨの範囲に調整すれば良いし、酸性側に有る場合には炭酸ナトリウム、苛性ソーダ等のアルカリを所定量添加すればよい。
【００１９】
分散液は、通常、ｐＨが４〜１０の間に有るように原料段階では調整するが、ｐＨの外乱要因が、ピリチオン亜鉛の粉砕工程や繊維の染色工程、繊維の機能性加工工程等にある。
即ち、本発明では、ピリチオン亜鉛を界面活性剤及び水の存在下、懸濁状態で粉砕することによりピリチオン亜鉛含有分散液を得る。この際、ボールミル、ハンマーミル等の粉砕器を使用することになるが、粉砕に当たっては、ピリチオン亜鉛が粉砕されるのみならず、僅かではあるが、装置側、即ち、ミルのボールやハンマーが削られ、分散液中に混入する。
【００２０】
ボールミル等の湿式粉砕装置では、セラミックボール、ガラスボール等からなる粉砕具が用いられるが、これらが微量削られて分散液に混入すると分散液はアルカリ性側に変化してしまう。
分散液がアルカリ性側になるとピリチオン亜鉛の分解が始まり、分散液の安定状態を保てない。
【００２１】
粉砕装置の材質によっては分散液が酸性側に変化する場合もあり、この場合にもピリチオン亜鉛の分解が始まり、分散液の安定状態を保てない。
酸性側に変化した場合には、上述した炭酸ナトリウム、苛性ソーダ等のアルカリを添加して、ｐＨが４〜１０、好ましくは５．５〜８．５の間に有るように調整すればよい。
【００２２】
粉砕装置として、分散液のｐＨを変化させない、即ち、粉砕の際全くそれ自体が削られず、分散液中に混入することがない材質からなる粉砕装置を用いるか、切削されてもｐＨを変化させない中性の材質からなる粉砕装置を用いるかすればこのような問題は生じないが、現実的には、効率的に粉砕が可能な装置で、ｐＨを変化させない材質からなる粉砕機は見出していない。
【００２３】
このようにして得られたピリチオン亜鉛の分散液は、取り扱い上、保管容量等の点から、通常ピリチオン亜鉛を４〜８０重量％含有した分散液とされるが、実際に繊維処理用に用いる分散液はこの濃い分散液を希釈した所謂「加工液」とされて用いられる。
実際に繊維加工に用いる加工液は、用途目的に応じ、そのまま、もしくは適当に希釈して用いるが、通常は加工液中のピリチオン亜鉛濃度を０．００１重量％〜４重量％未満に調製して用いる。処理法において具体的に述べると、浴中法では加工液中のピリチオン亜鉛が０．００１〜０．２重量％程度の濃度になるように、気中法の場合は加工液中のピリチオン亜鉛が０．０５〜４重量％程度好ましくは０．１〜２重量％程度の濃度になるように希釈して用いるのが良い。
【００２４】
この繊維処理用に用いる分散液（加工液）はそれ単独で繊維に適用しても良いが、通常は繊維を染色する際や難燃処理する際に併用して用いられることが多い。このような場合、染料や難燃処理剤やそれらの助剤がピリチオン亜鉛分散液（加工液）と混合されることになるので、染料や難燃処理剤やそれらの助剤のｐＨによってはｐＨの外乱要因となる。
【００２５】
ｐＨが４〜１０を外れると、前述もしたが、ピリチオン亜鉛の分解が始まり、分散液（加工液）の安定状態を保てない。また加工性（処理効率）も低下する。このような場合にも、ｐＨの調製が必要になる。
次に、繊維にピリチオン亜鉛を強力な耐洗濯性を備えた状態で、担持させるための要因としてはピリチオン亜鉛の粒径も影響する。しかも、単なる粒径ではなく、懸濁状態で粉砕する際の粒径コントロールが重要な意味を持つ。
【００２６】
ピリチオン亜鉛を乾燥状態で微粉砕し、水等の溶媒に分散させて分散液とすることもできるが、このような手段を用いた場合、ピリチオン亜鉛の粉末が一部再凝集したりして粒度分布が乱れ、種々の粒径のピリチオン亜鉛を含有する分散液となってしまう。
このような粒度分布の乱れたピリチオン亜鉛分散液を用いて、繊維類の抗菌・抗カビ加工を行っても、ピリチオン亜鉛が繊維間や繊維分子間に入り込めず加工効率が悪い。また、耐洗濯性の低いものしか得られない。
【００２７】
これは、凝集した大粒子が自体が繊維分子間に入り込めないことは勿論、他の細粒が繊維分子間に入り込もうとする（染み込む）のを妨害するためと推測される。
また、細かすぎる粒子は、工業的に不利になるほど相当長時間粉砕を行わなければならないし、再凝集しやすくなることが考えられる。
【００２８】
本発明の分散液は、ピリチオン亜鉛を界面活性剤及び水の存在下、懸濁状態で粉砕することにより、再凝集を防止しつつ、繊維分子間に旨く固定される大きさ、即ち、大きすぎも小さすぎもしないピリチオン亜鉛粒子が分散された分散液を得る。
分散液中のピリチオン亜鉛は、平均粒径が０．１〜１μｍ、好ましくは０．３〜０．７μｍであって、２μｍ以上の粒径のピリチオン亜鉛が全ピリチオン亜鉛に対し５重量％以下、好ましくは３重量％以下、更に好ましくは１重量％以下、となるように粉砕するのが良い。
【００２９】
ピリチオン亜鉛を界面活性剤と水との存在下、このような粒径範囲とすることにより、繊維類に適用すると、ピリチオン亜鉛が繊維間や繊維分子間に入り込み、しかも脱落することなく固定されやすい状態の分散液となる。
しかも、この分散液は、分散液中のピリチオン亜鉛濃度を４〜８０重量％とすることにより、粒径と濃度のバランスから、粉砕された粒子が再び凝集することが少なく、また、比較的長期に渡って安定した分散液状態を保つ。
【００３０】
分散液中のピリチオン亜鉛の粒径は、ＪＩＳ Ｒ１６２９に準拠してレーザー回折粒度分布測定装置を用いて測定したものであり、平均粒径とは累積５０％に相当するメジアン径を意味する。
次に、分散液の着色を防ぎ、更に分散液の安定状態を保ち、繊維に対するピリチオン亜鉛の固定率を向上させるための処方として、分散液（濃度４〜８０重量％の分散液）中の鉄及び銅の含有率をピリチオン亜鉛に対して０．１重量％以下、好ましくは０．０１重量％以下、更に好ましくは０．００１重量％以下とするのも有効である。
【００３１】
分散液に鉄や銅が混入すると、ピリチオン亜鉛の一部がピリチオン鉄やピリチオン銅に変化してしまう。
このピリチオン鉄やピリチオン銅の量が増加すると、即ち、鉄及び銅の含有率がピリチオン亜鉛に対して０．１重量％を越えると、分散液に発色を生じ、繊維加工の際着色という問題を生じるし、分散液の安定性や繊維の加工性（処理効率）にも問題を生じる。
【００３２】
なお、上述したように、繊維加工用に用いる分散液（加工液）はピリチオン亜鉛濃度が４〜８０重量％の分散液を希釈して用いるがこの場合には、ピリチオン亜鉛に対する鉄や銅の量が希釈前の分散液中の濃度より高濃度になっても着色が分散媒によって希釈されて使用可能となる場合もある。
場合によっては加工液中の鉄及び銅の含有率はピリチオン亜鉛に対して２０重量％程度まで、通常は２重量％程度まで許容される場合がある。
【００３３】
原料段階では鉄、銅等の２価の金属はピリチオン亜鉛の亜鉛以外入らないように調整するが、外乱要因が、粉砕工程や原料系にある。
即ち、本発明では、ピリチオン亜鉛を界面活性剤及び水の存在下、懸濁状態で粉砕することによりピリチオン亜鉛含有分散液を得る。この際、ボールミル、ハンマーミル等の粉砕器を使用することになるが、粉砕に当たっては、ピリチオン亜鉛が粉砕されるのみならず、僅かではあるが、装置側、即ち、ミルのボールやハンマーが削られ、分散液中に混入する。
【００３４】
ボールミル等の粉砕装置として金属製のボール等を用いた場合は上述したｐＨの外乱要因と同じように、粉砕具が微量削られて分散液に混入する原因となる。
前述したが、分散液に鉄や銅が混入すると、ピリチオン亜鉛の一部がピリチオン鉄やピリチオン銅に変化し、分散液に発色を生じ、繊維加工の際着色という問題を生じるし、分散液の安定性や繊維の加工性にも問題を生じる。
【００３５】
また、分散液や加工液の分散媒として用いる水に由来する鉄、銅の混入も考えられ、分散媒として用いる水は活性炭、イオン交換樹脂等で処理して、鉄や銅等の２価の金属を取り除いた水を用いるのが望ましい。
ピリチオン亜鉛の粉砕の際、水と共に用いる界面活性剤としては、脂肪酸せっけん、アルキルベンゼンスルホン酸塩、ナフタレンスルホン酸ホルマリン縮合物、ポリアクリル酸ナトリウム、リグニンスルフォン酸ナトリウム等の陰イオン界面活性剤、アルキルベンジルアンモニウム塩、アルキルアンモニウム塩等の陽イオン界面活性剤、長鎖アルキルアミノ酸、アルキルベタイン等の両性界面活性剤、ポリオキシエチレンノニルフェニルエーテル、ポリオキシエチレン硬化ヒマシ油等の非イオン界面活性剤が用途に応じ適宜用い得る。
【００３６】
界面活性剤の使用量としては、通常、分散液中０．５〜１０重量％程度である。
ピリチオン亜鉛含有分散液はピリチオン亜鉛を界面活性剤及び水の存在下、懸濁状態で粉砕することにより得るが、水性懸濁液形の原液を調製する際に、ナフタレンスルホン酸塩やリグニンスルホン酸塩等のアニオン系分散剤、スチレン化フェノール、ポリオキシエチレン・硬化ヒマシ油等の非イオン系分散剤、第４級アンモニウム塩系のカチオン系分散剤又はこれらの混合物からなる分散剤を用いても良い。
【００３７】
更に、必要に応じて増粘剤、凍結防止剤及び消泡剤等を加えても良い。
ピリチオン亜鉛を用いて繊維類を処理する方法としては、繊維類を上記１に記載のピリチオン亜鉛含有分散液もしくはその希釈液に浸漬し、常圧又は加圧下、８０〜１６０℃で浴中で加熱処理（浴中法）するか、または前記繊維類に前記分散液もしくはその希釈液を含浸又は付着させ、次いで１１０〜２３０℃で気中で加熱処理（気中法）することにより行われる。
【００３８】
上記のピリチオン亜鉛含有分散液は取り扱いの安定性等から濃度を４〜８０重量％としてあるが、実際に繊維加工に用いる場合は、用途目的に応じ、そのまま、もしくは適当に希釈して用いる。
前述したが、通常は浴中法では加工液中のピリチオン亜鉛が０．００１〜０．２重量％程度の濃度になるように、気中法の場合は加工液中のピリチオン亜鉛が０．０５〜４重量％程度の濃度になるように希釈して用いるのが良い。
【００３９】
ピリチオン亜鉛含有分散液は繊維加工に用いる場合、通常、水性乳化液あるいは水性懸濁液の形で適用される。
本発明による繊維類の抗菌・抗カビ加工は以下の様な方法により行われる。
まず、抗菌・抗カビ加工を加圧下に行う場合こは耐圧密閉容器中に、被加工繊維重量に対し０．００１〜２０重量％程度になるようにピリチオン亜鉛を入れ、これに繊維類を浸し（浴中法）、０〜６２０ＫＰａ程度の圧力下８０〜１６０℃で加熱処理する。
【００４０】
気中下に行う場合には開放容器中でピリチオン亜鉛含有分散液錯体を用い、被加工繊維重量に対し０．００１〜２０重量％程度になるようにピリチオン亜鉛を入れ、これに繊維類を浸すか、噴霧等により付着させ、これを気中に取り出し、乾燥の要領で乾熱もしくは場合により湿熱を用い１１０〜２３０℃で気中で加熱処理する。
【００４１】
繊維類の抗菌・抗カビ加工は繊維の種類によって条件が多少変わるが、ポリエステル繊維の場合は加圧下、１００〜１４０℃程度の温度で、ナイロン、アセテート又はアクリル繊維の場合は常圧下、８０〜１００℃程度の温度で処理することが望ましい。
いずれの場合も処理時間は３０秒から２時間程度でよい。
【００４２】
このようにすることにより本発明のピリチオン亜鉛は良好に繊維類の繊維分子間に入り込み、旨く固定される。
繊維が加熱されることにより、繊維の分子間が開いた状態となり、分散液中の溶解状態にあるピリチオン亜鉛がこの分子間に入り込み、かつ脱落しないように固定されるものと考えられる。
【００４３】
【実施例】
次に、実施例により、本発明を更に具体的に説明するが、本発明はこれら実施例に限定されるものではない。
なお、実施例中の、洗濯法や各種試験方法は、次の方法に従った。
１．洗濯法
１）ＪＩＳ Ｌ０２１７−１０３（４０℃の家庭洗濯）ＪＩＳ Ｌ１０４２−Ｆ２（６０℃のエ業洗濯）
２）ＪＡＦＥＴ特定制菌加工の洗濯法（ＪＡＦＥＴ標準配合洗剤を使用して、８０℃で５０回の洗濯を繰り返す。なお、本実施例では１００回の洗濯も実施した。
【００４４】
２．抗菌性試験
１）抗細菌性試験
黄色ブドウ球菌２種（Ｓｔａｐｈｙｌｏｃｏｃｃｕｓ ａｕｒｅｕｓ ＦＤＡ２０９Ｐ及びメチシリン耐性黄色ブドウ球菌：ＭＲＳＡ）、肺炎桿菌（Ｋｌｅｂｓｉｅｌｌａ ｐｎｅｕｍｏｎｉａｅ ＩＦＯ１３２７７），大腸菌２種（Ｅｓｃｈｅｒｉｃｈｉａ ｃｏｌｉ ＩＦ０３３０１及びＥ．ｃｏｌｉ Ｏ１５７：Ｈ７）及び緑膿菌（Ｐｓｅｕｄｏｍｏｎａｓ ａｅｒｕｇｉｎｏｓａ ＩＦＯ３７５５）について、ＪＡＦＥＴの統一試験法により、無加工布及び加工布の生菌数を測定した。
【００４５】
抗菌評価の判定は、各試験布の回収菌数が接種菌数未満の場合を有効(○)、以上の場合を無効（×）とした。
なお、表中、黄色ブドウ球菌はＳ、メチシリン耐性黄色ブドウ球菌はＭ、大腸菌はＥ、病原性大腸菌Ｏ１５７：Ｈ７はＥＯ、肺炎桿菌はＫ及び緑膿菌はＰとそれぞれ略記した。
【００４６】
２）抗かび性試験
ＪＩＳ Ｚ２９１１の繊維製品のカビ抵抗性試験法に従って以下の判定に従って評価した。
・試料又は試験片の接種した部分に菌糸の発育が認められない。・・・３
・試料又は試験片の接種した部分に認められる菌糸の発育部分の面積は、全面積の１／３を超えない。・・・２
・試料又は試験片の接種した部分に認められる菌糸の発育部分の面積は、全面積の１／３を超える。・・・１
３．測定法
１）粒径測定
分散液中のピリチオン亜鉛の粒径は、ＪＩＳ Ｒ１６２９に準拠してレーザー回折粒度分布測定装置を用いて測定した。
【００４７】
平均粒径とは累積５０％に相当するメジアン径を意味する。
２）処理効率
分散液を用いて繊維類を処理後繊維に吸着されたピリチオン亜鉛量（残った加工液中のピリチオン亜鉛量から逆算）の元の加工液中のピリチオン亜鉛量に対する比率（％）
実施例１
ピリチオン亜鉛（アーチ・ケミカルズ社製粉末状態、粒径ほぼ０．０２５ｍｍ）を２０重量部、ポリオキシエチレン硬化ヒマシ油（分散剤）を３重量部、ポリアクリル酸ソーダ（増粘剤）を０．５重量部、グリセリン（凍結防止剤）を２重量部、水を７４．５重量部用意し、ボールミル（ガラス製ボール使用）に仕込み、粉砕を行った。
【００４８】
粉砕開始時点の溶液のｐＨは６．５であったが、１２時間粉砕した後のｐＨは１０．５となった。この時点で、ｐＨを調節するため酢酸を添加し、ｐＨを８．０に調節した。
得られた分散液中のピリチオン亜鉛濃度は２０重量％であり、均一な分散状態を示した。この分散液の一部を１リットルの容器に移し、２４時間放置したが、極端な分離は認められなかった。
【００４９】
粉砕後のピリチオン亜鉛の平均粒径は０．５μｍで、２μｍ以上の粒径のピリチオン亜鉛は全ピリチオン亜鉛に対して０．５重量％であった。
分散液中の鉄及び銅の含有率は全ピリチオン亜鉛に対して０．００１重量％であった。この鉄分は使用した水に由来するものと考えられる。
ポリエステル織布（表中、Ｔと略記する）、ポリエステル・綿８５／１５混織布（表中、Ｔ／Ｃと略記する）、トリアセテート織布（表中、Ａと略記する）、ナイロン織布（表中、ＮＹと略記する）及びアクリル織布（表中、ＡＣと略記する）それぞれに対して上記で得られた分散液を用い、抗菌・抗カビ加工を施した。
【００５０】
加工液はピリチオン亜鉛が加工液中０．０４重量％、浴比（繊維重量：加工液重量）が１：１０となるように水で希釈して用いた。
加工条件は、ポリエステル及びポリエステル綿混は１３５℃、６０分とした。また、トリアセテート、ナイロン及びアクリルは９０℃、６０分とした。
加工後、水洗、還元洗浄（ポリエステルのみ）、水洗を施し、１３０℃、２分間乾燥した。なお、ポリエステル織布とポリエステル・綿８５／１５混織布については、１９０℃、３０秒間のヒートセットを行った後に工業洗濯を１００回を行った。トリアセテート織布、ナイロン織布及びアクリル織布については家庭洗濯を１００回行った。
【００５１】
得られた織布それぞれに抗菌性試験を行った。
抗菌性評価は抗菌・抗カビ加工した全ての織布において（○）であった。
ブランクとして、抗菌・抗カビ加工しなかった全ての種類の織布についての抗菌性評価を調べたが全て（×）であり、またカビ抵抗性は全て（１）であった。
表１に評価結果を纏めた。
【００５２】
【表１】

【００５３】
表１の記載から明らかなように、本発明の分散液は処理効率が極めて高い事、安定性に極めて優れることが分かる。
また、本発明の方法に従って加工処理の施された各織布は過酷な条件下の洗濯後も十分な抗菌性を発揮していることが分る。
実施例２
実施例１のｐＨ調製時、酢酸の添加量を変えｐＨを９．５に調製した。
【００５４】
実施例１と同様の試験を行ったところ、全ての織布について実施例１と同程度の抗菌性、抗カビ性を示した。
実施例３
実施例１のｐＨ調製時、酢酸の添加量を変えｐＨを４．５に調製した。
実施例１と同様の試験を行ったところ、全ての織布について実施例１と同程度の抗菌性、抗カビ性を示した。
比較例１
実施例１において、ｐＨの調節を行わなかった以外は実施例１と同様にして分散液を得た。
【００５５】
粉砕後のピリチオン亜鉛の濃度は１９．５重量％であり、平均粒径は０．５μｍで、２μｍ以上の粒径のピリチオン亜鉛は全ピリチオン亜鉛に対し０．５重量％であったがｐＨは１０．５であった。
この分散液の一部を１リットルの容器に移し、４０℃で放置したところ、ピリチオン亜鉛は分解し、１０日後には１重量％に減少した。また、分散液は着色し綿状の凝集物が観察された。
【００５６】
上記で得られた分散液（４０℃放置品）を用い、ポリエステル織布に抗菌・抗カビ加工を施した。
加工液は、ピリチオン亜鉛が加工液中０．００２重量％（浴比１：１０）となるようにに水で希釈して用いた。
加工条件は、１３５℃、６０分とした。
【００５７】
加工後、ポリエステル織布に水洗、還元洗浄、水洗を施し、１３０℃、２分間乾燥した。
得られた織布それぞれに抗菌性試験を行ったが、抗菌性は認められたが（抗菌性評価いずれも○）、処理効率が大変悪く、カビ抵抗性も「１」であった。
【００５８】
【発明の効果】
本発明によれば、抗菌・抗カビ処理用の分散液として処理効率が極めて高く、安定性に極めて優れる分散液が提供される。また、ポリエステル、アクリル、ナイロン、アセテートといった人造繊維製品及びこれらと天然繊維との混合繊維製品に対してＭＲＳＡはじめ黄色ブドウ球菌、大腸菌、緑膿菌等の菌及びかびに対して抗菌抗かび性を発揮する加工処理を施すことができ、付与された抗菌・抗かび性は、過酷な洗濯にも十分耐える。[0001]
BACKGROUND OF THE INVENTION
The present invention includes synthetic fibers such as polyester fibers, acrylic fibers and nylon fibers, and semi-synthetic fibers such as acetate fibers, and further, natural fibers, or synthetic fibers, mixed fibers of semi-synthetic fibers and natural fibers. The present invention relates to a pyrithione zinc-containing dispersion that imparts antibacterial and antifungal properties to the resulting fiber product, and a method for antibacterial and antifungal processing of fibers using the dispersion.
[0002]
In particular, a dispersion for imparting antibacterial properties against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae, Escherichia coli, pathogenic Escherichia coli O157, and Pseudomonas aeruginosa and the like were used for these textile products. The present invention relates to a processing method. The present invention also relates to a dispersion that is excellent in stability and handleability as a dispersion, and can impart antibacterial and antifungal properties with extremely high washing resistance to fibers, and a processing method using the dispersion.
[0003]
[Prior art]
Along with the growing hygiene-oriented nature of textile products such as clothing, futon covers, curtains, towels, wall cloth (wallpaper), etc., the development of antibacterial and antifungal treatments for various textile products is thriving.
In addition, the so-called nosocomial infection problem in the medical field has been greatly highlighted in recent years, and as a countermeasure, surgical clothing, sheets, duvet covers, partitions, force-tens, white robes, nightclothes, etc. Research on antibacterial and antifungal processing technologies is urgently needed.
[0004]
In antibacterial and antifungal processing technology for products made of synthetic fibers, etc., synthetic fibers are kneaded with antibacterial and antifungal agents in the spinning stock solution, and then spun to produce fibers with antibacterial and antifungal properties. Manufacture and mix it with other fibers as necessary to obtain a product, or synthetically-spun or semi-synthetic fibers that are spun normally or mixed with other fibers as necessary There is a method in which an antibacterial agent or an antifungal agent is adhered (impregnated) to the obtained cloth or a product obtained by sewing it.
[0005]
The antibacterial agent or antifungal agent can be attached to the fiber by immersing the fiber or fiber product in a solution containing the antibacterial agent or antifungal agent and holding it under pressure. There are a method of impregnating a solution containing an agent and then heating, and a method of adhering an antibacterial agent or an antifungal agent to a fiber or a fiber product using an adhesive component such as a binder resin and drying and fixing.
[0006]
[Problems to be solved by the invention]
However, the effect of antibacterial and antifungal processed products by any of these methods is weakened by new resistant bacteria that appear one after another, and the textile products used in medical facilities are for safety reasons for preventing infection. In order to wash strongly, it is required to provide antibacterial and antifungal properties with stronger washing resistance.
[0007]
Methicillin-resistant staphylococci, the so-called MRSA and recently the emergence of more resistant bacteria such as vancomycin-resistant enterococci (VRE); Development of new antibacterial and antifungal processing technology that can withstand severe industrial washing such as processing and hospital linen supply is awaited.
[0008]
The present inventors previously conducted extensive research on methods for imparting antibacterial and antifungal properties to polyester fiber products, and developed extremely effective methods (see Japanese Patent Publication No. 5-12475). After all, in research to further develop based on this result, I found a very effective method.
The present invention can impart strong antibacterial properties to fibers mainly composed of synthetic fibers against MRSA, Staphylococcus aureus, Escherichia coli, pathogenic Escherichia coli O157: H7, Pseudomonas aeruginosa and the like. It is an object of the present invention to provide a new pyrithione zinc-containing dispersion and a method for processing fibers having wash resistance using the dispersion.
[0009]
[Means for Solving the Problems]
The gist of the present invention is a pyrithione zinc-containing dispersion for antibacterial and antifungal processing obtained by grinding pyrithione zinc in a suspended state in the presence of a surfactant and water, and the dispersion is either during grinding or The main point is a pyrithione zinc-containing dispersion for antibacterial and antifungal processing, characterized in that the pH is adjusted between 4 and 10 after pulverization, and the concentration of pyrithione zinc in the dispersion is 4 to 80% by weight. A pyrithione zinc-containing dispersion for antibacterial and antifungal processing as described above, and a concentration of pyrithione zinc in the dispersion is adjusted to 0.001 wt% to less than 4 wt%, and the pH is 4 to 10 The above-described dispersion containing pyrithione zinc for antibacterial and antifungal processing, characterized in that the dispersion prepared in the meantime is used as a dispersion for fiber processing.
[0010]
Further, the fibers are immersed in the above-described pyrithione zinc-containing dispersion or a diluted solution thereof, and heat-treated in a bath at 80 to 160 ° C. under normal pressure or pressure, or the fibers are subjected to the dispersion or Another aspect of the gist is an antibacterial / antifungal processing method for fibers, which comprises impregnating or adhering the diluted solution and then heat-treating in the air at 110 to 230 ° C.
[0011]
Hereinafter, the present invention will be described in detail.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The fibers that can use the pyrithione zinc-containing dispersion of the present invention include natural fibers such as cotton, polyester fibers, nylon fibers, synthetic fibers such as polyacrylonitrile fibers, semi-synthetic fibers such as acetate fibers, and mixed fibers Is mentioned.
[0013]
Examples of fiber forms include yarns, knitted fabrics, woven fabrics, cloths, and various products. Examples of products include clothing, bedding, rugs, curtains, indoor wall cloths, and the like, particularly in medical facilities such as hospitals. Products such as surgical clothes, nursing clothes, bedding such as sheets and covers, partition curtains, bandages, towels, and towels.
As the antibacterial / antifungal agent used in the present invention, pyrithione zinc is used. The pyrithione zinc is a compound represented by the following formula [1].
[0014]
[Chemical 1]

[0015]
Pyrithione zinc has the characteristics that zinc is an essential component of the human body and has high safety, and the compound containing zinc (Zn) is hardly absorbed from the skin.
[0016]
Due to these characteristics, pyrithione zinc has a track record of being widely used in the field of cosmetics and hair washing agents.
Although pyrithione zinc is usually in a powder form, the fibers cannot be used for antibacterial / antifungal processing as they are.
That is, it is necessary to make the pyrithione zinc in a special state in order to carry the pyrithione zinc on the fiber in a state having strong washing resistance.
[0017]
The first major requirement is that the dispersion of the pyrithione zinc or the fiber processing dispersion diluted with this dispersion (hereinafter sometimes referred to as “processing fluid”), which is the pH of the dispersion, from the predetermined range to the alkaline side or If it shifts to the acidic side, the decomposition of pyrithione zinc proceeds and the desired efficacy tends not to be obtained, and a stable dispersion (including processing liquid) is not obtained over time.
[0018]
In order to maintain a stable state for a long period of time and to improve the fixing rate of pyrithione zinc to the fiber, the dispersion (including “processing liquid”) is preferably between 4 and 10, preferably during the pulverization or after pulverization. It is desirable to adjust between 5.5 and 8.5, more preferably between 6 and 8.
When the pH of the dispersion is on the alkaline side, the pH can be adjusted by adding a predetermined amount of an acid such as acetic acid, hydrochloric acid, phosphoric acid, etc., and adjusting to the above pH range. May be added with a predetermined amount of alkali such as sodium carbonate or caustic soda.
[0019]
The dispersion is usually adjusted at the raw material stage so that the pH is between 4 and 10, but the pH disturbance factors are in the pyrithione zinc grinding process, fiber dyeing process, fiber functional processing process, etc. .
That is, in the present invention, pyrithione zinc-containing dispersion is obtained by grinding pyrithione zinc in a suspended state in the presence of a surfactant and water. At this time, a pulverizer such as a ball mill or a hammer mill is used. In the pulverization, not only the pyrithione zinc is pulverized but also the apparatus side, that is, the mill ball or hammer is ground slightly. Mixed in the dispersion.
[0020]
In a wet pulverization apparatus such as a ball mill, a pulverizing tool made of ceramic balls, glass balls, or the like is used. However, if these are slightly cut and mixed into the dispersion, the dispersion changes to the alkaline side.
When the dispersion is on the alkaline side, the decomposition of pyrithione zinc begins and the dispersion cannot be kept stable.
[0021]
Depending on the material of the pulverizer, the dispersion may change to the acidic side, and in this case as well, decomposition of pyrithione zinc starts and the dispersion cannot be kept stable.
In the case of changing to the acidic side, an alkali such as sodium carbonate or caustic soda may be added to adjust the pH to be between 4 and 10, and preferably between 5.5 and 8.5.
[0022]
As the pulverizer, the pH of the dispersion is not changed, that is, the pulverizer is made of a material that is not cut at the time of pulverization and is not mixed in the dispersion, or the pH is not changed even when it is cut. If a pulverizer made of a neutral material is used, such a problem does not occur. However, in reality, there is no pulverizer made of a material that can efficiently pulverize and does not change pH.
[0023]
The pyrithione zinc dispersion thus obtained is usually a dispersion containing 4 to 80% by weight of pyrithione zinc in terms of handling and storage capacity. However, the dispersion is actually used for fiber treatment. The liquid is used as a so-called “processing liquid” obtained by diluting this thick dispersion.
The working fluid actually used for fiber processing is used as it is or appropriately diluted depending on the purpose of use. Usually, the concentration of pyrithione zinc in the working fluid is adjusted to 0.001 wt% to less than 4 wt%. Use. Specifically, in the treatment method, in the bath method, the pyrithione zinc in the processing liquid is about 0.001 to 0.2% by weight so that the concentration of pyrithione zinc in the processing liquid is about 0.001 to 0.2% by weight. It is good to dilute and use it at a concentration of about 0.05 to 4% by weight, preferably about 0.1 to 2% by weight.
[0024]
The dispersion liquid (processing liquid) used for fiber treatment may be applied to the fiber alone, but is usually often used in combination when dyeing the fiber or flame-treating. In such a case, since the dye, the flame retardant agent and their auxiliary agent are mixed with the pyrithione zinc dispersion (processing liquid), depending on the pH of the dye, the flame retardant agent and their auxiliary agent, the pH It becomes a disturbance factor.
[0025]
When the pH deviates from 4 to 10, as described above, the decomposition of pyrithione zinc starts and the stable state of the dispersion (processing liquid) cannot be maintained. In addition, workability (processing efficiency) also decreases. Even in such a case, it is necessary to adjust the pH.
Next, the particle diameter of pyrithione zinc also affects as a factor for supporting the pyrithione zinc in the fiber with strong washing resistance. Moreover, it is important to control the particle size when pulverizing in a suspended state, not just the particle size.
[0026]
Although pyrithione zinc can be finely pulverized in a dry state and dispersed in a solvent such as water to form a dispersion, when such means is used, the powder of pyrithione zinc may partially reagglomerate and The distribution is disturbed, resulting in a dispersion containing pyrithione zinc having various particle sizes.
Even when antibacterial and antifungal processing of fibers is performed using such a pyrithione zinc dispersion having a disturbed particle size distribution, the processing efficiency is poor because pyrithione zinc cannot enter between fibers or fiber molecules. Also, only those with low washing resistance can be obtained.
[0027]
This is presumed to be because the aggregated large particles cannot permeate themselves between the fiber molecules and of course prevent other fine particles from entering (infiltrating) between the fiber molecules.
In addition, too fine particles must be pulverized for a considerable time so as to be industrially disadvantageous, and may easily re-aggregate.
[0028]
The dispersion of the present invention has a size that is fixed between fiber molecules in a fine manner while preventing re-aggregation by pulverizing pyrithione zinc in the presence of a surfactant and water, in a suspended state. A dispersion in which pyrithione zinc particles that are neither too small nor too small is dispersed is obtained.
The pyrithione zinc in the dispersion has an average particle size of 0.1 to 1 μm, preferably 0.3 to 0.7 μm, and the pyrithione zinc having a particle size of 2 μm or more is 5% by weight or less based on the total pyrithione zinc, It is preferable to grind so that it is preferably 3% by weight or less, more preferably 1% by weight or less.
[0029]
By applying pyrithione zinc in such a particle size range in the presence of a surfactant and water, when applied to fibers, pyrithione zinc enters between fibers and between fiber molecules and is easily fixed without falling off. It becomes a dispersion of the state.
Moreover, this dispersion has a pyrithione zinc concentration in the dispersion of 4 to 80% by weight, whereby the pulverized particles are less likely to agglomerate again from the balance between the particle size and the concentration. A stable dispersion state is maintained throughout.
[0030]
The particle diameter of pyrithione zinc in the dispersion is measured using a laser diffraction particle size distribution measuring device in accordance with JIS R1629, and the average particle diameter means a median diameter corresponding to a cumulative 50%.
Next, iron in the dispersion (dispersion with a concentration of 4 to 80% by weight) is used as a prescription for preventing coloring of the dispersion, further maintaining the dispersion in a stable state, and improving the fixation ratio of pyrithione zinc to the fiber. It is also effective to adjust the copper content to 0.1% by weight or less, preferably 0.01% by weight or less, more preferably 0.001% by weight or less with respect to zinc pyrithione.
[0031]
When iron or copper is mixed into the dispersion, part of pyrithione zinc is changed to pyrithione iron or pyrithione copper.
When the amount of pyrithione iron or pyrithione copper increases, that is, when the content of iron and copper exceeds 0.1% by weight with respect to pyrithione zinc, a color develops in the dispersion, which causes a problem of coloring during fiber processing. This also causes problems in the stability of the dispersion and the processability (processing efficiency) of the fibers.
[0032]
As described above, the dispersion (processing liquid) used for fiber processing is diluted with a dispersion having a pyrithione zinc concentration of 4 to 80% by weight. In this case, the amount of iron or copper with respect to the pyrithione zinc is used. In some cases, the coloring becomes diluted with a dispersion medium and can be used even when the concentration becomes higher than the concentration in the dispersion before dilution.
In some cases, the content of iron and copper in the working fluid may be allowed up to about 20% by weight, usually up to about 2% by weight with respect to pyrithione zinc.
[0033]
In the raw material stage, adjustment is made so that divalent metals such as iron and copper do not enter other than zinc of pyrithione zinc, but there are disturbance factors in the grinding process and raw material system.
That is, in the present invention, pyrithione zinc-containing dispersion is obtained by grinding pyrithione zinc in a suspended state in the presence of a surfactant and water. At this time, a pulverizer such as a ball mill or a hammer mill is used. In the pulverization, not only the pyrithione zinc is pulverized but also the apparatus side, that is, the mill ball or hammer is ground slightly. Mixed in the dispersion.
[0034]
When a metal ball or the like is used as a pulverizing apparatus such as a ball mill, the pulverizing tool is scraped in a small amount and mixed into the dispersion liquid as in the case of the above-described pH disturbance factor.
As described above, when iron or copper is mixed into the dispersion, part of pyrithione zinc is changed to pyrithione iron or pyrithione copper, causing coloration in the dispersion and causing a problem of coloring during fiber processing. Problems also arise in stability and processability of the fibers.
[0035]
In addition, iron and copper derived from water used as a dispersion medium for the dispersion liquid and processing liquid may be mixed. The water used as the dispersion medium is treated with activated carbon, an ion exchange resin, or the like, and divalent such as iron or copper. It is desirable to use water from which metal has been removed.
Surfactants used together with water when grinding pyrithione zinc include fatty acid soap, alkylbenzene sulfonate, naphthalene sulfonate formalin condensate, anionic surfactants such as sodium polyacrylate and sodium lignin sulfonate, alkylbenzyl Cationic surfactants such as ammonium salts and alkylammonium salts, amphoteric surfactants such as long-chain alkyl amino acids and alkylbetaines, nonionic surfactants such as polyoxyethylene nonylphenyl ether and polyoxyethylene hydrogenated castor oil Can be used as appropriate.
[0036]
The amount of the surfactant used is usually about 0.5 to 10% by weight in the dispersion.
A dispersion containing zinc pyrithione is obtained by pulverizing zinc pyrithione in the presence of a surfactant and water in a suspended state, but when preparing an aqueous suspension-type stock solution, naphthalene sulfonate or lignin sulfonic acid is used. An anionic dispersant such as a salt, a nonionic dispersant such as styrenated phenol, polyoxyethylene / hardened castor oil, a quaternary ammonium salt cationic dispersant or a mixture thereof may be used. good.
[0037]
Furthermore, you may add a thickener, an antifreezing agent, an antifoamer, etc. as needed.
As a method of treating fibers using zinc pyrithione, the fibers are immersed in the pyrithione zinc-containing dispersion described in 1 above or a diluted solution thereof and heated in a bath at 80 to 160 ° C. under normal pressure or pressure. It is carried out by treatment (in-bath method), or by impregnating or adhering the dispersion or a diluted solution thereof to the fibers and then heat-treating in the air at 110 to 230 ° C. (in-air method).
[0038]
The above-mentioned pyrithione zinc-containing dispersion has a concentration of 4 to 80% by weight from the viewpoint of handling stability and the like, but when actually used for fiber processing, it is used as it is or after being appropriately diluted depending on the purpose of use.
As described above, usually, in the bath method, the concentration of pyrithione zinc in the processing liquid is about 0.001 to 0.2% by weight. It is preferable to dilute and use it to a concentration of about 4% by weight.
[0039]
When the pyrithione zinc-containing dispersion is used for fiber processing, it is usually applied in the form of an aqueous emulsion or aqueous suspension.
The antibacterial and antifungal processing of fibers according to the present invention is performed by the following method.
First, when antibacterial / antifungal processing is performed under pressure, put pyrithione zinc in a pressure-resistant airtight container so as to be about 0.001 to 20% by weight with respect to the processed fiber weight, and immerse the fibers in this. (In-bath method), heat treatment is performed at 80 to 160 ° C. under a pressure of about 0 to 620 KPa.
[0040]
When performing in the air, use a pyrithione-zinc-containing dispersion complex in an open container, and add pyrithione zinc to about 0.001 to 20% by weight with respect to the processed fiber weight, and immerse the fibers in this. It is attached by spraying or the like, taken out in the air, and heated in the air at 110 to 230 ° C. using dry heat or, in some cases, wet heat in the manner of drying.
[0041]
The conditions for the antibacterial and antifungal processing of fibers vary somewhat depending on the type of fiber, but in the case of polyester fiber, under pressure, at a temperature of about 100-140 ° C., in the case of nylon, acetate or acrylic fiber, under normal pressure, 80- It is desirable to process at a temperature of about 100 ° C.
In either case, the processing time may be about 30 seconds to 2 hours.
[0042]
By doing in this way, the pyrithione zinc of this invention penetrate | invades well between the fiber molecules of fibers, and is fixed well.
When the fiber is heated, the intermolecular state of the fiber is opened, and it is considered that pyrithione zinc in a dissolved state in the dispersion liquid enters the intermolecular state and is fixed so as not to fall off.
[0043]
【Example】
EXAMPLES Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
In addition, the washing | cleaning method and various test methods in an Example followed the following method.
1. Laundry method 1) JIS L0217-103 (40 ° C household laundry) JIS L1042-F2 (60 ° C industrial laundry)
2) Washing method of JAFET specific antibacterial processing (JAFET standard combination detergent was used and washing was repeated 50 times at 80 ° C. In this example, washing was performed 100 times.
[0044]
2. Antibacterial test 1) Antibacterial test 2 Staphylococcus aureus FDA209P and methicillin-resistant Staphylococcus aureus: MRSA, Klebsiella pneumoniae IFO 13277, E. coli 7 ) And Pseudomonas aeruginosa IFO3755, the number of viable bacteria in the unprocessed cloth and the processed cloth was measured by the unified test method of JAFET.
[0045]
The determination of antibacterial evaluation was valid (◯) when the number of recovered bacteria on each test cloth was less than the number of inoculated bacteria, and invalid (×) when the number was above.
In the table, S. aureus is abbreviated as S, methicillin-resistant Staphylococcus aureus is abbreviated as M, E. coli is abbreviated as E, pathogenic E. coli O157: H7 is abbreviated as EO, K. pneumoniae is abbreviated as K, and P. aeruginosa is abbreviated as P.
[0046]
2) Antifungal property test According to the following judgment according to the fungus resistance test method of the textile product of JIS Z2911.
・ No hyphal growth is observed in the inoculated part of the sample or test piece. ... 3
-The area of the growing part of the mycelium observed in the inoculated part of the sample or test piece does not exceed 1/3 of the total area. ... 2
-The area of the growth part of the mycelium recognized in the inoculated part of the sample or the test piece exceeds 1/3 of the total area. ... 1
3. Measurement Method 1) Particle Size Measurement The particle size of pyrithione zinc in the dispersion was measured using a laser diffraction particle size distribution measuring device in accordance with JIS R1629.
[0047]
The average particle diameter means a median diameter corresponding to 50% cumulative.
2) The ratio (%) of the amount of pyrithione zinc adsorbed on the fibers after treating the fibers with the treatment efficiency dispersion (counting backward from the amount of remaining pyrithione zinc in the processing fluid) to the amount of pyrithione zinc in the original processing fluid
Example 1
20 parts by weight of pyrithione zinc (powdered by Arch Chemicals, particle size of approximately 0.025 mm), 3 parts by weight of polyoxyethylene hydrogenated castor oil (dispersing agent), and sodium polyacrylate (thickening agent) of 0. 5 parts by weight, 2 parts by weight of glycerin (freezing agent) and 74.5 parts by weight of water were prepared, charged in a ball mill (using glass balls), and pulverized.
[0048]
The pH of the solution at the start of pulverization was 6.5, but the pH after pulverization for 12 hours was 10.5. At this point, acetic acid was added to adjust the pH and the pH was adjusted to 8.0.
The concentration of zinc pyrithione in the obtained dispersion was 20% by weight, indicating a uniform dispersion state. A portion of this dispersion was transferred to a 1 liter container and allowed to stand for 24 hours, but no extreme separation was observed.
[0049]
The average particle diameter of the pyrithione zinc after pulverization was 0.5 μm, and the pyrithione zinc having a particle diameter of 2 μm or more was 0.5% by weight based on the total pyrithione zinc.
The content of iron and copper in the dispersion was 0.001% by weight with respect to the total pyrithione zinc. This iron is thought to be derived from the water used.
Polyester woven fabric (abbreviated as T in the table), polyester / cotton 85/15 mixed woven fabric (abbreviated as T / C in the table), triacetate woven fabric (abbreviated as A in the table), nylon woven fabric Antibacterial and antifungal treatments were applied to the acrylic woven fabric (abbreviated as AC in the table) and the dispersion obtained as described above for each (abbreviated as NY in the table).
[0050]
The working fluid was diluted with water so that zinc pyrithione was 0.04 wt% in the working fluid and the bath ratio (fiber weight: working fluid weight) was 1:10.
The processing conditions were such that polyester and polyester cotton blends were 135 ° C. for 60 minutes. Triacetate, nylon and acrylic were set at 90 ° C. for 60 minutes.
After the processing, washing with water, reduction washing (polyester only) and washing with water were performed, followed by drying at 130 ° C for 2 minutes. In addition, about the polyester woven fabric and the polyester / cotton 85/15 mixed woven fabric, industrial washing was performed 100 times after heat setting at 190 ° C. for 30 seconds. Triacetate woven fabric, nylon woven fabric and acrylic woven fabric were washed 100 times at home.
[0051]
Each obtained woven fabric was subjected to an antibacterial test.
The antibacterial evaluation was (◯) for all woven fabrics processed with antibacterial and antifungal treatment.
As a blank, the antibacterial evaluation of all types of woven fabrics which were not subjected to antibacterial / antifungal processing was examined, all were (×), and all the mold resistance was (1).
Table 1 summarizes the evaluation results.
[0052]
[Table 1]

[0053]
As is apparent from the description in Table 1, it can be seen that the dispersion of the present invention has a very high processing efficiency and an extremely excellent stability.
It can also be seen that each woven fabric processed according to the method of the present invention exhibits sufficient antibacterial properties even after washing under severe conditions.
Example 2
During the pH adjustment in Example 1, the pH was adjusted to 9.5 by changing the amount of acetic acid added.
[0054]
When the same test as in Example 1 was performed, all the woven fabrics exhibited antibacterial and antifungal properties comparable to those in Example 1.
Example 3
During the pH adjustment in Example 1, the pH was adjusted to 4.5 by changing the amount of acetic acid added.
When the same test as in Example 1 was performed, all the woven fabrics exhibited antibacterial and antifungal properties comparable to those in Example 1.
Comparative Example 1
In Example 1, a dispersion was obtained in the same manner as Example 1 except that the pH was not adjusted.
[0055]
The concentration of pyrithione zinc after pulverization was 19.5% by weight, the average particle size was 0.5 μm, and pyrithione zinc having a particle size of 2 μm or more was 0.5% by weight based on the total pyrithione zinc, but the pH was 10.5.
When a part of this dispersion was transferred to a 1 liter container and left at 40 ° C., the pyrithione zinc was decomposed and decreased to 1% by weight after 10 days. The dispersion was colored and cotton-like aggregates were observed.
[0056]
The polyester woven fabric was subjected to antibacterial / antifungal treatment using the dispersion liquid obtained above (stored at 40 ° C.).
The working liquid was used after diluting with water so that zinc pyrithione was 0.002% by weight (bath ratio 1:10) in the working liquid.
The processing conditions were 135 ° C. and 60 minutes.
[0057]
After processing, the polyester woven fabric was washed with water, reduced and washed, and dried at 130 ° C. for 2 minutes.
An antibacterial test was carried out on each of the obtained woven fabrics. Although antibacterial properties were observed (both antibacterial properties were evaluated), the treatment efficiency was very poor and the mold resistance was “1”.
[0058]
【The invention's effect】
According to the present invention, a dispersion having extremely high processing efficiency and extremely excellent stability as a dispersion for antibacterial / antifungal treatment is provided. In addition, it has antifungal and antifungal properties against man-made fiber products such as polyester, acrylic, nylon, acetate and mixed fiber products of these and natural fibers against fungi such as MRSA, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa Processing can be performed, and the antibacterial and antifungal properties imparted can withstand harsh washing.

Claims (3)

  The pyrithione zinc is pulverized in a suspended state in the presence of a surfactant and water, and a zinc-containing pyrithione-containing dispersion whose pH is regulated between 5.5 and 8.5 during or after the pulverization is prepared. Dilute the zinc-containing dispersion and create a dispersion for pyrithione zinc-containing fiber processing whose pH is regulated between 5.5 and 8.5, and immerse the fibers in this dispersion for fiber processing containing pyrithione zinc Heat treatment in a bath at 80 to 160 ° C. under normal pressure or under pressure, or impregnate or attach the above-mentioned dispersion for pyrithione-containing fiber processing to fibers, and then heat in air at 110 to 230 ° C. An antibacterial / antifungal processing method for fibers characterized by processing.   The pyrithione zinc concentration of the above-mentioned pyrithione zinc-containing fiber processing dispersion is 0.001 to 4% by weight, and the average particle size of the pyrithione zinc in the pyrithione zinc-containing fiber processing dispersion is 0.3 to 0.7 μm. The antibacterial / antifungal processing method for fibers according to claim 1, wherein pyrithione zinc having a particle size of 2 µm or more is 5 wt% or less based on total pyrithione zinc. It said zinc pyrithione-containing zinc pyrithione concentration in the dispersion is, antifungal processing method fibers according to claim 1, characterized in that a 4 to 80 wt%.