JP4208433B2 - Absorbent articles - Google Patents

Description

【００１４】
前記高吸収性ポリマーとしては、前記の特性を満足するものであれば特に制限されないが、具体的には例えば、ポリアクリル酸ソーダ、（アクリル酸−ビニルアルコール）共重合体、ポリアクリル酸ソーダ架橋体、（デンプン−アクリル酸）グラフト重合体、（イソブチレン−無水マレイン酸）共重合体及びそのケン化物、ポリアクリル酸カリウム、並びにポリアクリル酸セシウム等が挙げられる。尚、前記の特性を満たすようにするためには、例えば、高吸収性ポリマーの粒子表面に架橋密度勾配を設けたり、高吸収性ポリマーの粒子を非球形状の不定形粒子とすればよく、具体的には特開平７−１８４９５６号公報の第７欄２８行〜第９欄第６行に記載の方法を用いることができる。
【００１５】
更に、本発明において用いられる高吸収性ポリマーは、以下の方法で測定される液通過時間が、２０秒以下、特に２〜１５秒であることが、ゲルブロッキングの発生及びそれに起因する吸収性能の低下を防止し、また、吸収が間に合わないことに起因する液の素抜けによる漏れの発生を防止する点から好ましい。
【００１６】
＜液通過時間の測定方法＞
断面積４．９１ｃｍ² （内径２５ｍｍφ）で底部に開閉自在のコック（内径４ｍｍφ）が設けられた円筒内に、該コックを閉鎖した状態で、高吸収性ポリマー０．５ｇを生理食塩水と共に充填し、該生理食塩水により該高吸収性ポリマーを飽和状態に達するまで膨潤させる。膨潤した該高吸収性ポリマーが沈降した後、該コックを開き、生理食塩水５０ｍｌを通過させる。該生理食塩水５０ｍｌが通過するのに要した時間を測定し、この時間を液通過時間とする。
【００１７】
高吸収性ポリマーは、５〜３００ｇ／ｍ² 、特に１００〜２５０ｇ／ｍ² 配合されていることが好ましい。ポリマーの量が３００ｇ／ｍ² を超えると前記不織布との絡み合いが十分でなくなり、ポリマーが移動し易くなり、また吸収性能の不安定化につながる。
【００１８】
本実施形態のおむつ１においては、表面材２に所定の植物エキスが施されている。植物エキスとしては、着用者の皮膚に対してスキンケア効果を有するものが用いられる。本明細書において、「スキンケア効果」とは、皮膚のかぶれ防止、消炎、抗菌等の皮膚の状態を正常にする効能全般を意味する。これに加えて、植物エキスとしては、吸収体４に含まれている高吸収性ポリマーに対して実質的に分解作用を有さないものが用いられる。「高吸収性ポリマーに対して実質的に分解作用を有さない」とは、高吸収性ポリマーに対して全く分解作用を有さない場合、及び高吸収性ポリマーの有する吸水性能を実質的に低下させない程度の低い分解作用を有する場合の双方を包含する。斯かる植物エキスを施すことで、着用者から排出された体液、例えば尿や汗によって起こり得る皮膚のかぶれや炎症が抑制され、またかぶれや炎症が起こった場合にそれらが治癒される。更に、吸収体４に含まれている高吸収性ポリマーの分解及びそれに起因する吸収性能の低下が防止される。高吸収性ポリマーの分解防止は、本実施形態に用いられている吸収体４のように、高吸収性ポリマーの吸収容量が高い場合（前述の遠心脱水法による吸水量が高い場合）に特に効果的である。
【００１９】
植物エキスは、表面材２から着用者の皮膚に移行して付着し得る状態で該表面材２に存在している。特に植物エキスは、水分と接触することでおむつ１から容易に離脱し、溶解又は分散するものであるか、又はそのような状態にあることが好ましい。具体的には、おむつ１が体液、例えば尿や汗と接触することによって該植物エキスが体液に拡散・溶解して該植物エキスに易動性が付与され、着用者の皮膚に移行して付着する状態で表面材２に存在していることが好ましい。植物エキスがこのような状態で存在していることで、植物エキスが移動し易くなり、容易に着用者の皮膚に達することができ、皮膚のかぶれや炎症が抑制され、またかぶれや炎症が起こった場合にそれらが迅速に治癒される。
【００２０】
植物エキスをこのような状態で存在させるには、例えば表面材２が不織布からなる場合、該不織布を構成する繊維に予め植物エキスを施しておき、植物エキスが施された繊維を原料として前記不織布を形成する方法が挙げられる。この場合、植物エキスは、界面活性剤の水溶液に混合しておき、混合により得られた混合液を前記繊維に付着させることで施される。
【００２１】
植物エキスを前記状態で存在させる別法として、表面材２に植物エキスを塗布する方法が挙げられる。この場合、植物エキスは、界面活性剤及び必要に応じ後述する浸透促進剤と混合しておき、混合により得られた混合液を表面材２に塗布することで施される。
【００２２】
植物エキスは、各種植物の全体又はその葉、樹皮、根及び枝のうちの一又は二以上の箇所を乾燥させ又は乾燥させることなく粉砕した後、常温又は加温下に溶剤によって抽出するか又はソックスレー抽出器等の抽出機具を用いて抽出することによって得られる。植物エキスとしては、スキンケア効果を有し且つ高吸収性ポリマーに対して実質的に分解作用を有さないものであれば特に制限無く用いることができる。特に、植物エキスとして、柚エキス、ハマメリスエキス、アスナロエキス、アロエエキス及びオウバクエキスから成る群から選択される一種以上の物質を用いることで、スキンケア効果が一層高くなり、また高吸収性ポリマーの分解が一層抑制される。これらのうちでも、スキンケア効果の更に一層の向上及び高吸収性ポリマーの更に一層の分解抑制の点から、ハマメリスエキス、アスナロエキス、柚エキスを用いることが好ましい。吸収性物品の製造工程で加熱処理を行う場合に防爆対応を要しない点から、前記植物エキスは、１，３−ブチレングリコール抽出物であることが好ましい。また、１，３−ブチレングリコール抽出物を用いることで、１，３−ブチレングリコールが植物エキスと共におむつ１中に共存することになり、吸収性能の劣化が少なくなる。
【００２３】
通常、植物エキスは、有効成分に加え溶剤成分及び水分を含んだ状態となっている。この状態での植物エキスの有効成分量（溶剤成分や水分を除いた量）は、０．００１〜５重量％であれば良い。但し、抽出用の溶剤成分として１，３−ブチレングリコールを用いた場合には、有効成分量と１，３−ブチレングリコールの量との総和が前記範囲内であればよい。特に、有効成分量は、溶剤成分の量に対して０．００１〜１０重量％であることが好ましい。
【００２４】
表面材２との摩擦に起因する皮膚の傷つきは、僅かな刺激物質に対してもかぶれを発生させる原因となる。そのため、植物エキスが施されている表面材２には不織布や織布などの軟らかな繊維集合体からなるシート材を用いることが好ましい。この観点から、繊維集合体を構成する繊維の太さは０．５〜５．５ｄｔｅｘ、特に１〜３．３ｄｔｅｘであることが好ましい。
【００２５】
表面材２として不織布を用いる場合には、その柔軟性を一層高めるために、構成繊維の融点よりも１０℃以内で高い温度で熱処理して不織布化することが望ましい。その場合、不織布の強度が低下し、おむつ１の製造や実使用上に支障を来す場合がある。そこで、不織布にエンボス処理を施すことによって、不織布の強度を向上させると共に肌との接触面積を上げて、植物エキスの移行量を増大させることが好ましい。エンボス処理する場合、エンボス面積率は、５〜５０％、特に１０〜３０％であることが、不織布の強度向上及び風合い低下の防止並びに接触面積の上がり過ぎに起因する皮膚とのべたつき防止の点から好ましい。
【００２６】
また、表面材２として不織布を用いる場合には、植物エキスを効果的に皮膚に移行させるために、該不織布の肌接触面側に多量の植物エキスを施すことが好ましい。このように植物エキスを施すには、不織布として二層以上の多層構造を有するエアスルー不織布を用い、肌接触面側である上層への植物エキスの配合量を高めることが望ましい。その場合、相対的に親水性処理剤の割合が低下することで、吸収性能の劣化につながるおそれがある。これを防ぐ目的で、肌非接触面側である下層に相対的に繊度の大きな繊維を用い、肌接触面側である上層に相対的に繊度の小さな複合繊維を用いることが好ましい。複合繊維としてサイド・バイ・サイド型や偏心芯鞘型の複合繊維を用いることで、繊維に立体捲縮がかかり、繊度が小さくても（＝風合いが優れる）、繊維間距離を大きくとることができ、吸収速度の向上が図れる。同様の考え方として、上層の一部に熱収縮繊維を混合しても良い。
【００２７】
植物エキスは、表面材２における少なくとも液の主吸収領域に施されている。「液の主吸収領域」とは、股下部からその前後方向へ延びる領域であり、表面材２における周縁部を除く意味である。勿論、表面材２の全面に亘って植物エキスが施されていてもよい。更には、立体ガード形成用の不織布、レッグ部、ウエスト部等の、おむつ内面における身体に接触し得る部分であれば、いずれの部分に施しても良い。
【００２８】
抽出方法や抽出溶媒によって異なるが、植物エキスは、表面材２の前記主吸収領域において、表面材２の該主吸収領域の重量に対して０．００５〜３重量％、特に０．０５〜１重量％施されていることが、安全性と効果とのバランス及び経済性の点から好ましい。
【００２９】
植物エキスが施されている部位、本実施形態においては表面材２に、植物エキスと共に該植物エキスの皮膚への浸透促進剤が施されていても良い。これによって、着用者の皮膚への植物エキスの浸透が促進され、皮膚のかぶれや炎症が一層抑制され、またかぶれや炎症が起こった場合にそれらが一層迅速に治癒される。
【００３０】
浸透促進剤としては、溶解度パラメータ値（以下、ＳＰ値という）が１５〜１７、特に１６〜１６．８の物質を用いることが好ましい。ＳＰ値が前記範囲内であることによって、べたつきが低くさらっとした感触のおむつとなる。
【００３１】
浸透促進剤としては、脂肪族エーテルや脂肪族エステルを用いることが好ましい。特に熱的に安定な物質である脂肪族エーテルを用いることが好ましい。この理由は、吸収性物品の製造工程においては一般に各構成部材の接合時に熱が付与され、その際に脂肪族エーテルは変性・分解しずらいからである。
【００３２】
特に好ましい浸透促進剤は、ミリスチル−１，３−ジメチルブチルエーテル、パルミチル−１，３−ジメチルブチルエーテル、ステアリル−１，３−ジメチルブチルエーテル、パルミチル−３−メチルプロピルエーテル、ステアリル−３−メチルプロピルエーテル等の脂肪族エーテルである。
【００３３】
本実施形態のおむつ１においては、植物エキスが施されている部位に、前述した浸透促進剤に加えてその他の成分を施してもよい。そのような成分としては、前記浸透促進剤のゲル化剤が挙げられる。前記浸透促進剤は、場合によっては吸収体４に含まれている高吸収性ポリマーの吸収性能を低下させるおそれがある。しかし、前記ゲル化剤によって前記浸透促進剤をゲル化させることで、該浸透促進剤が高吸収性ポリマーへ過度に拡散することが防止され、高吸収性ポリマーの吸収性能の低下が効果的に防止される。
【００３４】
前記ゲル化剤としては、前記浸透促進剤の拡散・移行を抑制し得る物質が用いられ、例えばパラフィンワックス、脂肪酸（Ｃ₁₂〜Ｃ₂₂）、脂肪族アルコール（Ｃ₁₂〜Ｃ₂₂）、ワセリン、脂肪酸ソルビタンエステル（モノ、ジ、トリ）、ポリオキシエチレン脂肪酸ソルビタンエステル等が挙げられる。
【００３５】
前記ゲル化剤は、前記浸透促進剤１００重量部に対して１０〜２００重量部、特に５０〜１００重量部施されていることが、経済性、触感、加工性の点から好ましい。
【００３６】
本実施形態のおむつ１においては、植物エキスが施されている部位に、前述した浸透促進剤及びゲル化剤に加えて別の成分を施してもよい。そのような成分としては、例えば前記植物エキス並びに必要に応じて用いられる前記浸透促進剤及び及び前記ゲル化剤を施す際に用いられる、これらの剤を含む混合物の粘度を調整するための粘度調整剤としての流動パラフィン、シリコーンオイル、動植物油（スクワラン、オリーブ油、ホホバ油、ベニバナ油）、モノ、ジ又はトリグリセライド等が挙げられる。前記植物エキス、前記浸透促進剤、前記ゲル化剤、及び前記粘度調整剤の混合物の常温（２０℃）におけるＪＩＳ硬度は２０〜５０であることが皮膚への植物エキスの移行性と触感とを両立できる点から好ましい。
【００３７】
本実施形態のおむつ１においては、前記植物エキスが施されている部位に、肌を滑らかにあるいは乾燥させる目的で、シッカロール、タルク、酸化チタン、シリコーンビーズ、ナイロンビーズ等の有機又は無機の微粒子を含有させても良い。該微粒子の粒径は０．０５〜５０μｍ、特に１〜２０μｍであることが前記目的が十分に達成される点から好ましい。
【００３８】
本発明は、前記実施形態に制限されない。例えば、植物エキスが着用者の皮膚に移行して付着し得る状態となるように該植物エキスを存在させる方法としては、前述の方法の他に以下の(1) 〜(5) の方法が例示される。
(1) おむつ１における弾性伸縮部材７が配された部位に植物エキスを施し、該植物エキスと皮膚との接触性を向上させることにより、該植物エキスを物理的に皮膚に移行させる方法。
(2) 常温で液体且つ実質的に不揮発性の物質、例えば保湿剤として知られている１，３−ブチレングリコール、グリセリン、プロピレングリコール、スクワラン、或いは前述の粘度調整剤と、植物エキスとを混合させて、該植物エキスの粘度を高めた状態で表面材２に施し、おむつ装着中の圧力によって表面材２から植物エキスを染み出させて皮膚に付着させる方法。
(3) 前述の有機又は無機の微粒子と、植物エキスとを混合させて、該植物エキスをペースト状或いは半固体状の状態で表面材２に施し、皮膚との接触によって前記微粒子ごと皮膚に移行・付着させる方法。
(4) 表面材２が不織布から構成されている場合、該不織布を構成する繊維に予め植物エキスを練り込んでおき、該植物エキスを繊維表面にブリードアウトさせて、皮膚に移行・付着させる方法。
(5) 植物エキスを多孔質粉体等に含浸させ、該多孔質粉体を表面材２に施し、植物エキスを該多孔質粉体表面にブリードアウトさせて、皮膚に移行・付着させる方法。
【００３９】
また、前記実施形態においては植物エキスを表面材２に施したが、これ代えて、またはこれと共に吸収体４の表面材側に植物エキスを施すことができる。吸収体４の表面材側に植物エキスを施す場合には、例えば吸収体４の表面材側に、水分活性が０．７以下となるように植物エキスを散布すればよい。
【００４０】
また吸収体４に、従来のおむつに一般的に用いられているパルプを含有させてもよい。この場合、パルプ１００重量部に対し、高吸収性ポリマーの量は５〜３００重量部であることが好ましい。
【００４１】
本発明の吸収性物品は、前述した使い捨ておむつに限られず、生理用ナプキン、失禁パッド、パンティライナー、おりものシート等の他の吸収性物品にも同様に適用できる。
【００４２】
【実施例】
以下の例中、特に断らない限り「％」及び「部」は、それぞれ「重量％」及び「重量部」を意味する。
【００４３】
〔実施例１〜３〕
実施例１では柚エキスのエタノール抽出液を３０部用いた。また実施例２及び３ではそれぞれハマメリスエキスの１，３−ブチレングリコール抽出液及びアスナロエキスの１，３−ブチレングリコールとエタノールとの混合抽出液を同様に３０部用いた。この部数の植物エキスと、ポリオキシエチレンアルキルエーテル（界面活性剤）７０部の５％水溶液とを均一に混合し、混合液を得た。芯がポリプロピレンで鞘がポリエチレンからなる偏心型芯鞘型複合繊維（２．２ｄｔｅｘ、５１ｍｍ）からなるエアスルー不織布の全面に前記混合液を塗布した。これにより植物エキスが施された表面材を得た。植物エキスの付着量（有効成分及び残存溶剤の合計量）はエアスルー不織布の重量に対して０．１５％であった。
【００４４】
これとは別に、レーヨン繊維（１．７ｄｔｅｘ、１５ｍｍ）と、ポリエチレンテレフタレート繊維（５．５ｄｔｅｘ、５１ｍｍ）とを重量比３０／７０の比率で混綿し、坪量４０ｇ／ｍ² のエアスルー不織布を作製した。この不織布上に、高吸水性ポリマーの粒子を２００ｇ／ｍ² の坪量となるように散布し、該不織布の繊維間に高吸水性ポリマー〔ポリアクリル酸ソーダ架橋体（遠心脱水法による吸水量５０ｇ／ｇ）〕の粒子を保持させた。次いで、この不織布上下面を坪量１５ｇ／ｍ² の薄葉紙で包んで吸収体を得た。
【００４５】
この吸収体の片面に前記表面材を配し、他の面に裏面材としてポリエチレン製フィルムを配した。更に、公知の止着具、弾性伸縮部材等を配して、図１に示す形態の使い捨ておむつを得た。
【００４６】
〔実施例４〕
実施例２で用いたエアスルー不織布に直径２ｍｍの円形模様のエンボス処理（エンボス率２５％）を施した不織布を用いた以外は実施例２と同様にして使い捨ておむつを得た。
【００４７】
〔比較例１〕
ヒバマタエキスの１，３−ブチレングリコール抽出液１部及びポリオキシエチレンアルキルエーテル２部の５％水溶液を均一に混合し、混合物を得た。芯がポリプロピレンで鞘がポリエチレンからなる芯鞘型複合繊維（２．２ｄｔｅｘ、５１ｍｍ）からなるエアスルー不織布の表面に前記混合物を塗布した。これにより植物エキスが施された表面材を得た。植物エキスの付着量は実施例１と同様とした。これ以外は実施例１と同様にして使い捨ておむつを得た。
【００４８】
〔比較例２〕
実施例１で用いたエアースルー不織布に植物エキスを配合しなかった以外は実施例１と同様にして使い捨ておむつを得た。
【００４９】
〔性能評価〕
実施例及び比較例で得られた使い捨ておむつを１０名のモニターに２週間使用して貰い、おむつかぶれの発生の有無及び使用後の高吸収性ポリマーの溶解の程度を評価した。その結果を表１に示す。
【００５０】
【表１】

【００５１】
表１に示す結果から明らかなように、実施例の使い捨ておむつ（本発明品）は、比較例のおむつに比して、おむつかぶれが抑制されていることが判る。また、高吸収性ポリマーの分解に起因する溶解も抑制されていることが判る。更に、表には示していないが、実施例の使い捨ておむつはべたつき感が無くさらっとした感触を呈していた。
【００５２】
【発明の効果】
本発明の吸収性物品によれば、高吸収性ポリマーの吸収性能を阻害せずに、着用者の皮膚のかぶれが効率的に抑制される。
【図面の簡単な説明】
【図１】本発明の吸収性物品の一実施形態としての使い捨ておむつを表面材側から見た一部破断平面図である。
【符号の説明】
１ 使い捨ておむつ（吸収性物品）
２ 表面材
３ 裏面材
４ 吸収体[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an absorbent article that efficiently suppresses the skin irritation of a wearer without inhibiting the absorption performance of the superabsorbent polymer.
[0002]
[Prior art and problems to be solved by the invention]
As an absorbent article for the purpose of preventing the wearer's skin irritation, for example, those described in Japanese Patent Application Laid-Open No. 10-509895 and Japanese Patent Application No. 10-509896 are known. These publications describe disposable diapers in which a lotion containing an emollient is applied to the top sheet. This lotion agent contains an immobilizing agent that immobilizes the emollient on the top sheet.
[0003]
However, in the disposable diaper described in the publication, since the emollient is immobilized on the top sheet, the emollient is not easily transferred to the wearer's skin. Therefore, the emollient applied to the top sheet is not efficient because the total amount cannot effectively contribute to the anti-inflammatory action of the skin. Further, the immobilizing agent added to immobilize the emollient itself may become a stimulating substance and cause rash. In addition, the lotion may become hard and cause small scratches on the skin, which may also cause irritation.
[0004]
In addition to the above-mentioned publications, there are known absorbent articles with medicinal ingredients for the purpose of preventing the wearer's skin irritation. However, in those absorbent articles, unless an appropriate medicinal component is selected, the cross-linked structure of the superabsorbent polymer is cleaved due to the medicinal component, resulting in a decrease in liquid absorption and liquid return. It will increase. An increase in the amount of liquid return causes skin wetting, which in turn promotes skin irritation. If the amount of the medicinal component is reduced to prevent this, the anti-rash effect is not exhibited.
[0005]
Therefore, an object of the present invention is to provide an absorbent article that can efficiently suppress the skin irritation of the wearer without inhibiting the absorption performance of the superabsorbent polymer.
[0006]
[Means for Solving the Problems]
The present invention relates to an absorbent article having a liquid-retaining absorbent layer and a liquid-impermeable leak-proof layer, wherein the absorbent layer contains a superabsorbent polymer. And a plant extract that does not substantially have a decomposing action on the superabsorbent polymer, and the plant extract is transferred to the skin of the wearer from the site and can be attached. The object is achieved by providing an existing absorbent article.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the absorbent article of the present invention will be described with reference to the drawings, taking a disposable diaper as an example of the absorbent article.
[0008]
As shown in FIG. 1, the disposable diaper 1 of the present embodiment includes a surface material 2 as a liquid-permeable surface layer made of a nonwoven fabric or a perforated film, and a back material 3 as a liquid-impermeable leak-proof layer. And an absorbent body 4 as a liquid retaining absorbent layer interposed between the front surface material 2 and the back surface material 3. The absorber 4 is formed in a curved hourglass shape with a constricted region corresponding to the crotch region of the diaper 1. The absorber 4 is sandwiched and fixed by the front surface material 2 and the back surface material 3.
[0009]
A back side and abdomen side waist portions 5 and 5 ′ and a pair of leg portions 6 and 6 formed by the front surface material 2 and the back surface material 3 extending outward from front and rear and left and right end edges of the absorber 4. When the diaper 1 is worn, the elastic elastic member 7 for fitting the waist portions 5 and 5 ′ and the leg portions 6 and 6 to the wearer's body is fixed by the surface material 2 and the back surface material 3. Is provided. A pair of fasteners 8 each composed of a tape fastener or the like are attached to both ends in the width direction of the back side waist portion 5, and a rectangular landing on the back material 3 in the waist portion 5 ′ on the abdomen side An attachment (not shown) made of tape or the like is attached. And when the disposable diaper 1 of this embodiment is worn, the fastening tools 8 and 8 are made to fasten on a to-be-attached tool. As these members constituting the diaper 1, the same members as those used in conventional disposable diapers are used.
[0010]
The absorbent body 4 has superabsorbent polymer particles and a nonwoven fabric. The superabsorbent polymer particles are held in the interfiber spacing of the nonwoven fabric. The entire surface of the nonwoven fabric holding the superabsorbent polymer particles is covered with the thin paper 11. Thus, the absorber 4 is configured. The absorbent body 4 having such a configuration is extremely thin as compared with a conventional absorbent body mainly composed of pulp and superabsorbent polymer particles. The fibers constituting the nonwoven fabric include rayon fibers, hydrophilic fibers such as cotton and cellulose acetate, polyolefin fibers such as polyethylene and polypropylene, condensed fibers such as polyester and polyamide, and vinyl monomer polymers such as vinyl chloride and vinyl acetate. And the like. Of these fibers, hydrophobic fibers may be used after being hydrophilized by treatment with an oil agent or the like.
[0011]
The superabsorbent polymer used in the present invention has a physiological saline water absorption amount of preferably 30 g / g or more, more preferably 30 to 45 g / g, still more preferably 35 to 45 g / g. . If a superabsorbent polymer having a water absorption of less than 30 g / g is used, it is necessary to increase the amount of the polymer in the absorbent body 4 in order to improve the absorption capacity, which is not economical and becomes a thick diaper. It may lack portability. The water absorption is measured by the following method.
[0012]
<Measurement method of water absorption by centrifugal dehydration of superabsorbent polymer>
After 1 g of superabsorbent polymer is swollen with 150 ml of physiological saline for 30 minutes, it is placed in a 250 mesh nylon mesh bag, dehydrated with a centrifuge at 143 G for 10 minutes, and the total weight after dehydration is measured. Next, the amount of water absorption (g / g) by centrifugal dehydration is calculated according to the following formula (1).
[0013]
[Expression 1]

[0014]
The superabsorbent polymer is not particularly limited as long as it satisfies the above-mentioned characteristics. Specifically, for example, polyacrylic acid soda, (acrylic acid-vinyl alcohol) copolymer, polyacrylic acid soda crosslinking Body, (starch-acrylic acid) graft polymer, (isobutylene-maleic anhydride) copolymer and saponified product thereof, potassium polyacrylate, and cesium polyacrylate. In order to satisfy the above characteristics, for example, a crosslink density gradient may be provided on the surface of the superabsorbent polymer particles, or the superabsorbent polymer particles may be non-spherical amorphous particles. Specifically, the method described in JP-A-7-18495, column 7 line 28 to column 9 line 6 can be used.
[0015]
Furthermore, the superabsorbent polymer used in the present invention has a liquid passage time measured by the following method of 20 seconds or less, particularly 2 to 15 seconds. It is preferable from the viewpoint of preventing a drop and preventing the occurrence of leakage due to the escape of liquid due to the inadequate absorption.
[0016]
<Measurement method of liquid transit time>
A cylinder with a cross-sectional area of 4.91 cm ² (inner diameter: 25 mmφ) and a cock that can be opened and closed at the bottom (inner diameter: 4 mmφ) is filled with 0.5 g of superabsorbent polymer together with physiological saline with the cock closed. And swell the superabsorbent polymer with the saline until it reaches saturation. After the swollen superabsorbent polymer settles, the cock is opened and 50 ml of physiological saline is passed through. The time required for 50 ml of the physiological saline to pass through is measured, and this time is taken as the liquid passage time.
[0017]
The superabsorbent polymer is preferably blended in an amount of 5 to 300 g / m ² , particularly 100 to 250 g / m ² . When the amount of the polymer exceeds 300 g / m ² , the entanglement with the non-woven fabric becomes insufficient, the polymer becomes easy to move, and the absorption performance becomes unstable.
[0018]
In the diaper 1 of the present embodiment, a predetermined plant extract is applied to the surface material 2. As the plant extract, those having a skin care effect on the skin of the wearer are used. In the present specification, the “skin care effect” means general effects for normalizing skin conditions such as skin irritation prevention, anti-inflammation and antibacterial effects. In addition to this, as the plant extract, one having substantially no decomposing action on the superabsorbent polymer contained in the absorber 4 is used. “Substantially has no decomposing action on the superabsorbent polymer” means that the water absorbing performance of the superabsorbent polymer is substantially the same as when the superabsorbent polymer has no decomposing action. It includes both cases where the decomposition action is low enough not to decrease. By applying such a plant extract, skin irritation and inflammation that can be caused by body fluids discharged from the wearer, such as urine and sweat, are suppressed, and when irritation and irritation occur, they are cured. Furthermore, the decomposition of the superabsorbent polymer contained in the absorbent body 4 and the deterioration of the absorption performance resulting therefrom are prevented. Prevention of decomposition of the superabsorbent polymer is particularly effective when the absorbent capacity of the superabsorbent polymer is high (when the amount of water absorption by the centrifugal dehydration method described above is high) like the absorbent body 4 used in the present embodiment. Is.
[0019]
The plant extract is present in the surface material 2 in a state where it can be transferred from the surface material 2 to the skin of the wearer and attached thereto. In particular, it is preferable that the plant extract is easily separated from the diaper 1 by contact with moisture, dissolved or dispersed, or in such a state. Specifically, when the diaper 1 comes into contact with a body fluid such as urine or sweat, the plant extract diffuses and dissolves in the body fluid, thereby imparting mobility to the plant extract, and moves to and adheres to the skin of the wearer. It is preferable that it exists in the surface material 2 in the state to do. The presence of the plant extract in this state makes it easier for the plant extract to move, easily reach the wearer's skin, suppresses skin irritation and inflammation, and causes irritation and inflammation. If they are healed quickly.
[0020]
In order for the plant extract to be present in such a state, for example, when the surface material 2 is made of a nonwoven fabric, the plant extract is applied in advance to the fibers constituting the nonwoven fabric, and the nonwoven fabric is made from the fibers with the plant extract as a raw material. The method of forming is mentioned. In this case, the plant extract is applied by mixing it in an aqueous solution of a surfactant and attaching the mixed solution obtained by mixing to the fibers.
[0021]
As another method for causing the plant extract to exist in the above state, a method of applying the plant extract to the surface material 2 can be mentioned. In this case, the plant extract is applied by mixing a surface active agent 2 with a surfactant and, if necessary, a penetration enhancer described later, and applying a mixed solution obtained by mixing to the surface material 2.
[0022]
The plant extract is pulverized without drying or drying one or more parts of the whole plant or its leaves, bark, roots and branches, and then extracted with a solvent at room temperature or under heating, or It can be obtained by extraction using an extractor such as a Soxhlet extractor. Any plant extract can be used without particular limitation as long as it has a skin care effect and has substantially no decomposing action on the superabsorbent polymer. In particular, as a plant extract, the use of one or more substances selected from the group consisting of camellia extract, hamamelis extract, asunalo extract, aloe extract, and alum extract, the skin care effect is further enhanced, and the superabsorbent polymer is decomposed. Is further suppressed. Among these, from the viewpoint of further improving the skin care effect and further suppressing the decomposition of the superabsorbent polymer, it is preferable to use a Hamelis extract, an asunalo extract, and a koji extract. The plant extract is preferably a 1,3-butylene glycol extract from the viewpoint that no explosion-proof treatment is required when heat treatment is performed in the manufacturing process of the absorbent article. Moreover, by using a 1, 3- butylene glycol extract, 1, 3- butylene glycol will coexist in the diaper 1 with a plant extract, and deterioration of absorption performance will decrease.
[0023]
Usually, a plant extract is in a state containing a solvent component and moisture in addition to an active ingredient. The amount of the active ingredient of the plant extract in this state (amount excluding the solvent component and moisture) may be 0.001 to 5% by weight. However, when 1,3-butylene glycol is used as the solvent component for extraction, the sum of the amount of the active ingredient and the amount of 1,3-butylene glycol may be within the above range. In particular, the amount of the active ingredient is preferably 0.001 to 10% by weight with respect to the amount of the solvent component.
[0024]
Skin damage caused by friction with the surface material 2 causes rash even for a slight irritant. Therefore, it is preferable to use a sheet material made of a soft fiber aggregate such as a nonwoven fabric or a woven fabric for the surface material 2 to which the plant extract is applied. From this viewpoint, the thickness of the fiber constituting the fiber assembly is preferably 0.5 to 5.5 dtex, particularly 1 to 3.3 dtex.
[0025]
When using a nonwoven fabric as the surface material 2, it is desirable to heat-treat at a temperature within 10 ° C. higher than the melting point of the constituent fibers to make the nonwoven fabric in order to further increase the flexibility. In that case, the strength of the nonwoven fabric may be reduced, which may hinder the production and actual use of the diaper 1. Therefore, it is preferable to increase the transfer amount of the plant extract by embossing the nonwoven fabric to improve the strength of the nonwoven fabric and increase the contact area with the skin. When embossing is performed, the embossed area ratio is 5 to 50%, particularly 10 to 30%, for improving the strength of the nonwoven fabric, preventing the texture from being lowered, and preventing the skin from sticking due to excessive increase in the contact area. To preferred.
[0026]
Moreover, when using a nonwoven fabric as the surface material 2, in order to transfer a plant extract to skin effectively, it is preferable to apply a lot of plant extracts to the skin contact surface side of this nonwoven fabric. In order to apply the plant extract in this manner, it is desirable to use an air-through nonwoven fabric having a multilayer structure of two or more layers as the nonwoven fabric and increase the blending amount of the plant extract into the upper layer on the skin contact surface side. In that case, the ratio of the hydrophilic treatment agent is relatively decreased, which may lead to deterioration in absorption performance. For the purpose of preventing this, it is preferable to use a relatively fine fiber for the lower layer on the skin non-contact surface side, and a relatively small composite fiber for the upper layer on the skin contact surface side. By using a side-by-side type or eccentric core-sheath type composite fiber as the composite fiber, even if the fiber is sterically crimped and the fineness is small (= excellent texture), the distance between fibers can be increased. And the absorption rate can be improved. As a similar idea, heat shrink fibers may be mixed in a part of the upper layer.
[0027]
The plant extract is applied to at least the main absorption region of the liquid in the surface material 2. The “liquid main absorption region” is a region extending from the crotch part in the front-rear direction and excluding the peripheral part of the surface material 2. Of course, the plant extract may be given over the entire surface material 2. Furthermore, as long as it is a part which can contact the body in the inner surface of a diaper, such as a nonwoven fabric for forming a three-dimensional guard, a leg part, and a waist part, it may be applied to any part.
[0028]
Although depending on the extraction method and the extraction solvent, the plant extract is 0.005 to 3% by weight, particularly 0.05 to 1% in the main absorption region of the surface material 2 with respect to the weight of the main absorption region of the surface material 2. It is preferable to be applied in terms of weight% from the viewpoint of the balance between safety and effect and economical efficiency.
[0029]
The site | part to which the plant extract is given, the surface material 2 in this embodiment may be given the penetration promoter to the skin of this plant extract with the plant extract. This promotes the penetration of the plant extract into the wearer's skin, further suppresses skin irritation and inflammation, and cures irritation more quickly when irritation or irritation occurs.
[0030]
As the penetration enhancer, it is preferable to use a substance having a solubility parameter value (hereinafter referred to as SP value) of 15 to 17, particularly 16 to 16.8. When the SP value is within the above range, the diaper has a low-stickiness and a dry feel.
[0031]
As the penetration enhancer, it is preferable to use an aliphatic ether or an aliphatic ester. In particular, it is preferable to use an aliphatic ether which is a thermally stable substance. This is because in the manufacturing process of the absorbent article, heat is generally applied at the time of joining the constituent members, and at that time, the aliphatic ether is difficult to modify and decompose.
[0032]
Particularly preferred penetration enhancers include myristyl-1,3-dimethylbutyl ether, palmityl-1,3-dimethylbutyl ether, stearyl-1,3-dimethylbutyl ether, palmityl-3-methylpropyl ether, stearyl-3-methylpropyl ether, and the like. Is an aliphatic ether.
[0033]
In the diaper 1 of this embodiment, you may give another component to the site | part to which the plant extract is given in addition to the penetration promoter mentioned above. Examples of such a component include a gelling agent for the penetration enhancer. In some cases, the penetration enhancer may reduce the absorption performance of the superabsorbent polymer contained in the absorbent body 4. However, gelation of the penetration enhancer with the gelling agent prevents the penetration enhancer from excessively diffusing into the superabsorbent polymer, effectively reducing the absorption performance of the superabsorbent polymer. Is prevented.
[0034]
As the gelling agent, a substance capable of suppressing the diffusion / migration of the penetration enhancer is used. For example, paraffin wax, fatty acid (C ₁₂ -C ₂₂ ), aliphatic alcohol (C ₁₂ -C ₂₂ ), petroleum jelly, Examples include fatty acid sorbitan esters (mono, di, tri), polyoxyethylene fatty acid sorbitan esters, and the like.
[0035]
The gelling agent is preferably applied in an amount of 10 to 200 parts by weight, particularly 50 to 100 parts by weight, based on 100 parts by weight of the penetration accelerator, from the viewpoints of economy, touch and workability.
[0036]
In the diaper 1 of this embodiment, you may give another component to the site | part to which the plant extract is given in addition to the penetration promoter and the gelatinizer mentioned above. Such components include, for example, the above-mentioned plant extract and the viscosity enhancer for adjusting the viscosity of a mixture containing these agents used when applying the penetration enhancer and the gelling agent used as necessary. Examples of the agent include liquid paraffin, silicone oil, animal and vegetable oils (squalane, olive oil, jojoba oil, safflower oil), mono-, di- and triglycerides. The mixture of the plant extract, the penetration enhancer, the gelling agent, and the viscosity modifier has a JIS hardness at room temperature (20 ° C.) of 20 to 50. It is preferable from the standpoint of compatibility.
[0037]
In the diaper 1 of the present embodiment, organic or inorganic fine particles such as siccalol, talc, titanium oxide, silicone beads, and nylon beads are added to the part where the plant extract is applied for the purpose of smoothing or drying the skin. It may be included. The particle diameter of the fine particles is preferably 0.05 to 50 μm, and particularly preferably 1 to 20 μm, from the viewpoint that the object is sufficiently achieved.
[0038]
The present invention is not limited to the embodiment. For example, the following methods (1) to (5) are exemplified in addition to the above-described methods as a method for causing the plant extract to be present in a state where the plant extract can migrate to and adhere to the wearer's skin. Is done.
(1) A method of physically transferring the plant extract to the skin by applying a plant extract to the portion of the diaper 1 where the elastic elastic member 7 is disposed and improving the contact between the plant extract and the skin.
(2) Mixing a plant extract with a liquid that is liquid at room temperature and substantially non-volatile, such as 1,3-butylene glycol, glycerin, propylene glycol, squalane, or the aforementioned viscosity modifier, known as a humectant. Then, the method is applied to the surface material 2 in a state in which the viscosity of the plant extract is increased, and the plant extract is exuded from the surface material 2 by the pressure during wearing of the diaper and adhered to the skin.
(3) The above organic or inorganic fine particles are mixed with a plant extract, and the plant extract is applied to the surface material 2 in a paste or semi-solid state, and transferred to the skin together with the fine particles by contact with the skin. -How to attach.
(4) When the surface material 2 is composed of a non-woven fabric, a method in which a plant extract is kneaded in advance into the fibers constituting the non-woven fabric, the plant extract is bleed out on the fiber surface, and transferred to and attached to the skin. .
(5) A method in which a plant extract is impregnated with a porous powder or the like, the porous powder is applied to the surface material 2, and the plant extract is bleed out on the surface of the porous powder to be transferred to and attached to the skin.
[0039]
Moreover, although the plant extract was applied to the surface material 2 in the said embodiment, a plant extract can be given to the surface material side of the absorber 4 instead of this or with this. When a plant extract is applied to the surface material side of the absorber 4, for example, the plant extract may be sprayed on the surface material side of the absorber 4 so that the water activity is 0.7 or less.
[0040]
Moreover, you may make the absorber 4 contain the pulp generally used for the conventional diaper. In this case, the amount of the superabsorbent polymer is preferably 5 to 300 parts by weight with respect to 100 parts by weight of the pulp.
[0041]
The absorbent article of the present invention is not limited to the disposable diaper described above, and can be similarly applied to other absorbent articles such as a sanitary napkin, an incontinence pad, a panty liner, a cage sheet, and the like.
[0042]
【Example】
In the following examples, “%” and “parts” mean “% by weight” and “parts by weight”, respectively, unless otherwise specified.
[0043]
[Examples 1-3]
In Example 1, 30 parts of an ethanol extract of koji extract was used. In Examples 2 and 3, 30 parts of a 1,3-butylene glycol extract of Hamameris extract and a mixed extract of 1,3-butylene glycol and ethanol of asunalo extract were used in the same manner. This part of the plant extract and a 5% aqueous solution of 70 parts of polyoxyethylene alkyl ether (surfactant) were uniformly mixed to obtain a mixed solution. The mixed solution was applied to the entire surface of an air-through nonwoven fabric composed of an eccentric core-sheath composite fiber (2.2 dtex, 51 mm) having a core of polypropylene and a sheath of polyethylene. This obtained the surface material to which the plant extract was given. The adhesion amount of the plant extract (total amount of active ingredients and residual solvent) was 0.15% with respect to the weight of the air-through nonwoven fabric.
[0044]
Separately, rayon fibers (1.7 dtex, 15 mm) and polyethylene terephthalate fibers (5.5 dtex, 51 mm) are mixed in a weight ratio of 30/70 to produce an air-through nonwoven fabric with a basis weight of 40 g / m ^2. did. On this nonwoven fabric, particles of a superabsorbent polymer are dispersed so as to have a basis weight of 200 g / m ² , and a superabsorbent polymer [polyacrylic acid soda crosslinked product (water absorption amount by centrifugal dehydration method) is formed between the fibers of the nonwoven fabric. 50 g / g)] particles were retained. Next, the upper and lower surfaces of the nonwoven fabric were wrapped with thin paper having a basis weight of 15 g / m ² to obtain an absorbent body.
[0045]
The said surface material was distribute | arranged to the single side | surface of this absorber, and the polyethylene film was distribute | arranged to the other surface as a back surface material. Furthermore, a known fastener, an elastic elastic member, etc. were arranged to obtain a disposable diaper having the form shown in FIG.
[0046]
Example 4
A disposable diaper was obtained in the same manner as in Example 2 except that a non-woven fabric obtained by subjecting the air-through nonwoven fabric used in Example 2 to a 2 mm diameter circular pattern embossing treatment (embossing rate 25%) was used.
[0047]
[Comparative Example 1]
A 5% aqueous solution of 1 part of 1,3-butylene glycol extract of Hibamata extract and 2 parts of polyoxyethylene alkyl ether was uniformly mixed to obtain a mixture. The said mixture was apply | coated to the surface of the air through nonwoven fabric which consists of a core-sheath-type composite fiber (2.2 dtex, 51 mm) whose core is a polypropylene and whose sheath is polyethylene. This obtained the surface material to which the plant extract was given. The amount of plant extract attached was the same as in Example 1. Except this, it carried out similarly to Example 1, and obtained the disposable diaper.
[0048]
[Comparative Example 2]
A disposable diaper was obtained in the same manner as in Example 1 except that the plant extract was not added to the air-through nonwoven fabric used in Example 1.
[0049]
[Performance evaluation]
The disposable diapers obtained in Examples and Comparative Examples were used on 10 monitors for 2 weeks to evaluate the occurrence of diaper rash and the degree of dissolution of the superabsorbent polymer after use. The results are shown in Table 1.
[0050]
[Table 1]

[0051]
As is clear from the results shown in Table 1, it can be seen that the disposable diaper of the example (the product of the present invention) is less susceptible to diaper rash than the diaper of the comparative example. Moreover, it turns out that the melt | dissolution resulting from decomposition | disassembly of a superabsorbent polymer is also suppressed. Further, although not shown in the table, the disposable diapers of the examples had no stickiness and had a dry feel.
[0052]
【The invention's effect】
According to the absorbent article of the present invention, the skin irritation of the wearer is efficiently suppressed without impairing the absorption performance of the superabsorbent polymer.
[Brief description of the drawings]
FIG. 1 is a partially broken plan view of a disposable diaper as an embodiment of an absorbent article of the present invention as viewed from a surface material side.
[Explanation of symbols]
1 disposable diaper (absorbent article)
2 Surface material 3 Back material 4 Absorber

Claims (4)

An absorbent article having a liquid-retaining absorbent layer and a liquid-impermeable leak-proof layer, wherein the absorbent layer contains a superabsorbent polymer, and having a skin care effect at a predetermined site of the absorbent article; the superabsorbent has been subjected to substantially no decomposition plant extract the polymer, the plant extract is present in a state capable of adhering proceeds to the wearer's skin from the site An absorbent article using at least one selected from the group consisting of a Hamamelis extract, an Asunaro extract and a koji extract as the plant extract .   The absorbent article according to claim 1, further comprising a liquid-permeable surface layer sandwiching the absorbent layer together with the leak-proof layer, wherein the plant extract is applied to the surface layer.   The absorptive article according to claim 1 in which said plant extract is given to said absorption layer. The absorbent article according to any one of claims 1 to 3 , wherein the superabsorbent polymer has a physiological water absorption of 30 g / g or more by centrifugal dehydration.

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