JP4406982B2 - Soap bar - Google Patents

Description

【０００７】
（式中、Ｒは水素またはメチル基を表し、Ｍはアルカリ金属、アンモニウム、有機アンモニウムのいずれかを表す。）を０.１〜２０重量％含有する固形石鹸に関する。
【０００８】
好ましい実施態様においては、上記固形石鹸には、さらにｃ成分として、炭素数８〜２２の脂肪酸とアミノ酸またはアミノ酸のアルカリ金属塩、アンモニウム塩、もしくは有機アンモニウム塩との塩を０.５〜１０重量％含有する。
【０００９】
【発明の実施の形態】
ａ成分である脂肪酸のアルカリ金属塩を構成する脂肪酸は、炭素数が８〜２２である。炭素数が７以下では速泡性および起泡性が低下し、溶け崩れしやすくなり、炭素数が２３以上では速泡性、起泡性および保存安定性が低下し、良好な使用感が得られない。炭素数が８〜２２の脂肪酸としては、例えば、カプリル酸、カプリン酸、ラウリン酸、ミリスチン酸、パルミチン酸、ステアリン酸、イソステアリン酸、オレイン酸、並びに脂肪酸の混合物であるヤシ油脂肪酸、パーム核油脂肪酸、牛脂脂肪酸などが挙げられる。ラウリン酸、ミリスチン酸、パルミチン酸などの飽和脂肪酸が速泡性や起泡性、保存安定性の点で特に好ましい。
【００１０】
これらの脂肪酸は、単独で用いてもよく、２種以上組み合わせて用いてもよい。中でも、ラウリン酸、ミリスチン酸およびパルミチン酸を組み合わせて用いる場合が好ましく、ラウリン酸を１５〜３５重量％、ミリスチン酸を５５〜７５重量％およびパルミチン酸を５〜２０重量％含有し、かつ、ラウリン酸、ミリスチン酸およびパルミチン酸の合計が９５〜１００重量％の脂肪酸が好ましく用いられる。
【００１１】
上記脂肪酸と塩を構成するアルカリ金属としては、ナトリウムまたはカリウムが挙げられる。アルカリ金属塩を作成する場合に用いるアルカリ剤としては金属水酸化物、金属炭酸化物などが挙げられる。アルカリ金属は、単独で用いてもよいし、２種以上組み合わせて用いてもよい。好ましい場合は、カリウムとナトリウムとを組み合わせて用い、カリウム/ナトリウムの重量比が１/４〜３/２の場合である。より好ましくは、１／２〜１／３である。
【００１２】
最も好ましいａ成分は、ラウリン酸、ミリスチン酸およびパルミチン酸を上記特定の割合で混合し、これとカリウム/ナトリウムの重量比が１/４〜３/２の金属アルカリ剤とから構成される脂肪酸アルカリ金属塩か、あるいは、ラウリン酸、ミリスチン酸およびパルミチン酸のナトリウム塩またはカリウム塩を上記比率になるように組み合わせて構成される脂肪酸アルカリ金属塩である。
【００１３】
ａ成分は、５０〜９５重量％、好ましくは５５〜９０重量％含有される。ａ成分が５０重量％未満では溶け崩れを起こしやすくなり、速泡性および起泡性が低下する。９５重量％を超えると、好ましい泡質、良好な使用感が得られず、溶解性および保存安定性が悪くなる。
【００１４】
ｂ成分としては、以下の式（１）で示される化合物：
【００１５】
【化３】

【００１６】
が用いられる。Ｒは水素またはメチル基を表し、Ｍはアルカリ金属、アンモニウム、有機アンモニウムのいずれかである。すなわち、Ｒが水素の場合は、ｂ成分はタウリンのアルカリ金属塩、アンモニウム塩、有機アンモニウム塩のいずれかである。Ｒがメチル基の場合は、メチルタウリンのアルカリ金属塩、アンモニウム塩、有機アンモニウム塩のいずれかである。これらのタウリン塩またはメチルタウリン塩は、単独で用いてもよいし、２種以上組み合わせて用いてもよい。
【００１７】
タウリンまたはＮ-メチルタウリンと塩を形成するアルカリ金属としては、ナトリウム、カリウムなどが挙げられる。また、有機アンモニウムとしては、モノエタノールアンモニウム、ジエタノールアンモニウム、トリエタノールアンモニウムなどが挙げられる。
【００１８】
ｂ成分は、０.１〜２０重量％、好ましくは０.５〜１５重量％含まれるが、ｂ成分が０.１重量％未満では好ましい泡質、良好な使用感が得られず、さらに溶解性が悪くなる。ｂ成分が２０重量％を超えると溶け崩れが起こりやすくなり、保存安定性が悪くなる。
【００１９】
本発明の固形石鹸には、さらにｃ成分として、炭素数８〜２２の脂肪酸とアミノ酸またはアミノ酸のアルカリ金属塩、アンモニウム塩もしくは有機アンモニウム塩との塩（以下、脂肪酸塩ということがある。）を含有することができる。ｃ成分の添加により、速泡性、起泡性、泡質を損なうことなく溶解性や保存安定性を向上させることができる。これらのｃ成分である脂肪酸塩は、単独で用いてもよく、２種以上組合せて用いてもよい。
【００２０】
ｃ成分の脂肪酸塩を構成する脂肪酸は、炭素数が８〜２２であり、例えばカプリル酸、カプリン酸、ラウリン酸、ミリスチン酸、パルミチン酸、ステアリン酸、イソステアリン酸、オレイン酸、並びに混合物であるヤシ油脂肪酸、パーム核油脂肪酸、牛脂脂肪酸などが挙げられる。ｃ成分の脂肪酸の炭素数が７以下では速泡性および起泡性が低下し、溶け崩れしやすくなり、炭素数が２３以上では速泡性、起泡性および保存安定性が低下し、良好な使用感が得られない。
【００２１】
ｃ成分の脂肪酸塩の形成に用いられるアミノ酸の例としてはアスパラギン酸、グルタミン酸などの酸性アミノ酸、グリシン、ザルコシン、アラニン、β-アラニン、フェニルアラニン、バリン、口イシン、イソロイシン、スレオニン、メチオニン、テアニン、セリン、プロリン、γ-アミノ酪酸、γ-アミノカプロン酸などの中性アミノ酸、アルギニン、オルニチン、ヒスチジン、リジン、トリプトファンなどの塩基性アミノ酸が挙げられる。
【００２２】
また、脂肪酸塩の形成に用いられるアミノ酸塩は、アミノ酸とアルカリ金属、アンモニウム、もしくは有機アンモニウムとの塩である。具体的には、アミノ酸とナトリウム、カリウム、アンモニウム、モノエタノールアンモニウム、ジエタノールアンモニウム、トリエタノールアンモニウムとの塩などが挙げられる。ｃ成分は、好ましくは、０.５〜１０重量％含有される。
【００２３】
なお、本発明の固形石鹸においては、洗浄時のきしみ感をさらに緩和する目的でクエン酸、酒石酸、リンゴ酸などのα-ヒドロキシ酸またはその塩、プロピレングリコール、ジプロピレングリコール、グリセリン、ジグリセリン、１、３-ブチレングリコール、ポリエチレングリコールなどの多価アルコールを本発明の効果を損なわない範囲で配合することができる。具体的にはクエン酸０.０３〜１重量％およびグリセリン０.１〜５重量％を添加することが好ましい。
【００２４】
さらに本発明の固形石鹸は、所望により一般に配合される成分、例えば、アルキルエーテルサルフェート型陰イオン性界面活性剤、アシルイセチオネート型陰イオン性界面活性剤、アシルメチルタウレート型陰イオン性界面活性剤、アミドエーテルサルフェート型陰イオン性界面活性剤、アシルアミノ酸塩型陰イオン性界面活性剤、アルキルエーテルカルボキシレート型陰イオン性界面活性剤などの陰イオン性界面活性剤、アルキルベタイン型両性界面活性剤、アミドベタイン型両性界面活性剤、イミダゾリニウムベタイン型両性界面活性剤、アミドアミノ酸型両性界面活性剤、アルキルグリシン型両性界面活性剤、アルキルイミノジ酢酸型両性界面活性剤、β-アルキルアミノプロピオン酸型両性界面活性剤、アルキルイミノジプロピオン酸型両性界面活性剤、アルキルジアミノエチルグリシン型両性界面活性剤、アルキルスルホベタイン型両性界面活性剤、アミドスルホベタイン型両性界面活性剤、アルキルホスホベタイン型両性界面活性剤などの両性界面活性剤、ポリオキシエチレンアルキルエーテル型非イオン性界面活性剤、ポリオキシエチレンアルキルフェニルエーテル型非イオン性界面活性剤、ポリオキシエチレン脂肪酸エステル型非イオン性界面活性剤、ソルビタンエステル型非イオン性界面活性剤、ポリオキシエチレンソルビタンエステル型非イオン性界面活性剤、ポリオキシエチレンポリオキシプロピレンアルキルエーテル型非イオン性界面活性剤、脂肪酸アルカノールアミド型非イオン性界面活性剤、ポリオキシエチレン脂肪酸アルカノールアミド型非イオン性界面活性剤、グリセリン脂肪酸エステル型非イオン性界面活性剤、ポリグリセリン脂肪酸エステル型非イオン性界面活性剤、アミンオキシド型非イオン性界面活性剤、アルキルグルコシド型非イオン性界面活性剤などの非イオン性界面活性剤、セチルアルコール、ステアリルアルコールなどの高級アルコール、スクワラン、ホホバ油、オリーブ油、ヒマシ油、ラノリン、レシチンなどの油分、セルロースエーテル型陽イオン性高分子化合物、陽イオン性ポリビニルピロリドン誘導体、陽イオン性ポリアクリル酸誘導体、陽イオン性ポリアミド誘導体、ポリ塩化ジメチルジアリルアンモニウム、塩化ジメチルジアリルアンモニウムとアクリル酸アミドの共重合体、アルキルポリエチレンイミンなどの陽イオン性高分子化合物、高重合メチルポリシロキサン、ジメチルシロキサン・メチル（ポリオキシエチレン）シロキサン共重合体などのシリコーン誘導体、カルボキシビニルポリマー、カルボキシメチルセルロース、ヒドロキシプロピルメチルセルロース、ヒドロキシエチルセルロースなどの水溶性高分子、パラオキシ安息香酸エステル、安息香酸ナトリウム、フェノキシエタノールなどの防腐剤、エチレンジアミン四酢酸塩、ニトリロトリ酢酸三ナトリウムなどのキレート剤、ベンゾフェノン誘導体、ベンゾトリアゾール誘導体などの紫外線吸収剤、動植物由来の天然エキス、その他、色素、香料などを本発明の効果を損なわない程度に含むことができる。
【００２５】
【実施例】
本発明を実施例により貝体的に説明する。
【００２６】
実施例における固形石鹸の調製法、試験法および評価法を以下に説明する。
【００２７】
（固形石鹸の調製法）
脂肪酸を５Ｌ双腕式混練機（入江商会（株）製ＰＮＶ-５型）に入れ、約８０℃に加熱し、２８重量％水酸化ナトリウム水溶液または２８重量％水酸化カリウム水溶液との混合液（Ｎａ／Ｋの重量比２／１〜３／１）を脂肪酸と当モル量添加して、８５〜９５℃で約５分間、攪拌混合した（ａ成分の調製）後、ｂ成分であるタウリン塩またはＮ-メチルタウリン塩、必要に応じて、ｃ成分である脂肪酸とアミノ酸塩との塩、その他の成分であるグリセリン、クエン酸などを添加し、更にその温度で攪拌混合を続けて乾燥させながら水分量を調節した。得られた組成物を押し出し機（（株）佐藤鉄工所製）を用いて、混練および押し出しを行ない、棒状石鹸を得た後、型打ち機（理研精機（株）製ＭＰ-２Ｂ型）で成形して固形石鹸を調製した。
【００２８】
（試験法および評価法）
（１）溶解性
得られた固形石鹸を底面積３ｃm^２の直方体に切断した。（株）蔵持化学器械製作所製の石鹸摩擦溶解度試験器を用いて、得られた直方体の石鹸の底面と水で馴染ませたフィルムとをフィルムを回転させることにより５分間摩擦させて重量（Ｗ１）を測定し、さらに再度、石鹸の底面と水で馴染ませたフィルムとを５分間摩擦させて重量（Ｗ２）を測定して、次式により摩擦溶解度を算出した。摩擦溶解度が１５以上の石鹸を溶解性の良好な固形石鹸であると評価した。なお、水温は４０℃で試験した。
摩擦溶解度＝〔（Ｗ１−Ｗ２）×１００〕/３
【００２９】
表１〜４では、摩擦溶解度が１５以上の場合を○、１５未満の場合を×で示した。
【００３０】
（２）起泡力
岩谷産業（株）製ミルサー（型番−ＦＭ−１００）のカップに人工硬水（炭酸カルシウム換算で１００ｐｐｍになるように塩化カルシウムとイオン交換水で調製）で調製した石鹸濃度０.２５重量％の水溶液を５０ｇとり、これに人工汚垢（オリーブ油５０重量％、オレイン酸２０重量％、ラノリン１０重量％、流動パラフィン１０重量％、スクワレン１０重量％からなる）を０.３ｇ添加してカップに蓋をし、４０℃で１時間静置した。１時間後、カップをミルサーにとりつけ、３０００ｒｐｍで５秒間攪拌し、攪拌停止から１分後の泡の高さを測定した。カップの最低位置からの泡の高さが９ｃｍ以上の場合を起泡力が高いと評価した。表１〜４では、泡の高さが９ｃｍ以上の場合を○で、９ｃｍ未満の場合を×で示した。
【００３１】
（３）泡の持続力
上記（２）の起泡力の測定において、攪拌停止から５分後の泡の高さを測定し、次の式から求めた数値が９０％以上の場合を泡の持続力が高いと評価した。
持続率（％）=［（５分後の泡の高さ）/（１分後の泡の高さ）］×１００
【００３２】
表１〜４では、持続率が９０％以上の場合を○で、９０％未満の場合を×で示した。
【００３３】
（４）速泡性
男女各１０名をパネラーとし、綿タオルを使用して固形石鹸を泡立てたときの泡の立ち方について評価した。泡が速やかに立ち、速泡性が良いと感じた場合を２点、泡が立つまで若干時間を要すると感じた場合を１点、泡が立つまで非常に時間を要し、速泡性が悪いと感じた場合を０点として２０名の合計点から、次の３段階で評価した。
○：速泡性が良好である（合計点３０点以上）。
△：速泡性がやや悪い（合計点２０点以上３０点未満）。
×：速泡性が悪い（合計点２０点未満）。
【００３４】
（５）泡質
男女各１０名をパネラーとし、固形石鹸で体を洗浄した時の泡質を評価した。泡が細かく弾力性があると感じた場合を２点、泡がやや粗いと感じた場合を１点、泡が粗く弾力性がないと感じた場合を０点として２０名の合計点から、次の３段階で評価した。
○：泡質が良好である（合計点３０点以上）。
△：泡質がやや悪い（合計点２０点以上３０点未満）。
×：泡質が悪い（合計点２０点未満）。
【００３５】
（６）洗浄時のきしみ感
男女各１０名をパネラーとし、固形石鹸で体を洗浄し、お湯で洗い流した時のきしみ感を評価した。きしみ感がないと感じた場合を２点、少しきしみ感があると感じた場合を１点、きしみ感が強いと感じた場合を０点として２０名の合計点から、次の３段階で評価した。
無 ：きしみ感がない（合計点３０点以上）。
やや有：少しきしみ感がある（合計点２０点以上３０点未満）。
有 ：きしみ感が強い（合計点２０点未満）。
【００３６】
（７）洗浄後の肌のつっぱり感
男女各１０名をパネラーとし、固形石鹸で体を洗浄した後の肌のつっぱり感を評価した。肌が全くつっぱらないと感じた場合を２点、少しつっぱると感じた場合を１点、非常につっぱると感じた場合を０点として２０名の合計点から、次の３段階で評価した。
無 ：つっぱり感がない（合計点３０点以上）。
やや有：少しつっぱり感がある（合計点２０点以上３０点未満）。
有 ：非常につっぱる（合計点２０点未満）。
【００３７】
（８）溶け崩れ
固形石鹸を２５℃の水中に１時間浸漬させた後、２時間乾燥し、２時間後に表面の状態を目視で観察して次の４段階で評価した。◎および○を溶け崩れのしにくい（耐溶け崩れ性のある）固形石鹸であると評価した。
◎：試験前の状態とほとんど変化がなく、十分硬さがあり溶け崩れを生じていない。
○：表面だけ柔らかく内部は固い状態であり、ほぼ溶け崩れを生じていない。
△：内部まで若干柔らかくなり、多少溶け崩れを生じている。
×：内部まで柔らかくなり、完全に溶け崩れを生じている。
【００３８】
（９）保存安定性
固形石鹸を４０℃の開放系で１ヶ月間保存し、その外観を観察して、次の３段階で評価した。
○：安定性良好（１ヶ月間外観および臭気の変化がない）
△：安定性やや不良（若干着色やひび割れを生じる、または臭気がやや劣化する）
×：安定性不良（着色やひび割れが著しい、または臭気の劣化が著しい）
【００３９】
実施例１〜１０および比較例１〜６
表１〜３に示す組成の固形石鹸を調製し、上記の評価法に従い評価を行った。結果を表１〜３に示す。
【００４０】
【表１】

【００４１】
【表２】

【００４２】
【表３】

【００４３】
表１〜３から、本発明の実施例１〜１０の固形石鹸は、溶解性が良好であり、速泡性および起泡性に優れ、非常に弾力性のある泡質を有し、洗浄時および洗いあがりの使用感が良好で、溶け崩れやひび割れを生じにくく、かつ保存安定性に優れた固形石鹸であることがわかる。
【００４４】
比較例１の固形石鹸はａ成分の含有量が５０重量％より少ないため、攪拌停止１分後の泡高さ、速泡性が悪く、溶け崩れしやすい。
【００４５】
比較例２の固形石鹸はａ成分の含有量が９５重量％を超えているため、溶解性が低く、好ましい泡質が得られず、洗浄時のきしみ感と洗浄後の肌のつっぱり感が強く、保存安定性が悪い。
【００４６】
比較例３の固形石鹸はｂ成分の含有量が０.１重量％より少ないため、溶解性と泡の持続率が低く、好ましい泡質が得られず、洗浄時のきしみ感と洗浄後の肌のつっぱり感が強い。
【００４７】
比較例４の固形石鹸はｂ成分の含有量が１０重量％を超えているため、溶け崩れしやすく、保存安定性が悪い。
【００４８】
比較例５の固形石鹸はｂ成分を含有せず、攪拌停止１分後の泡高さ、泡の持続率が低く、好ましい泡質が得られず、洗浄時のきしみ感が強く、保存安定性が悪い。
【００４９】
比較例６の固形石鹸はｂ成分を含有せず、溶解性、泡の持続率および速泡性が低く、好ましい泡質が得られず、洗浄時のきしみ感および洗浄後の肌のつっぱり感が強く、保存安定性が悪い。
【００５０】
実施例１１および比較例７
透明石鹸を以下の方法で調製し、上記の試験法および評価法に従って評価した。
【００５１】
（透明石鹸の調製方法）
脂肪酸を５Ｌ双腕式混練機（入江商会（株）製ＰＮＶ−５型）に入れ、約８０℃に加熱し、２８重量％の水酸化ナトリウムと水酸化カリウムとの混合水溶液（Ｎａ／Ｋの重量比が２／１）を脂肪酸と当モル量添加して８５〜９５℃で約５分間攪拌混合した（ａ成分の調製）後、実施例１１にはｂ成分であるタウリンナトリウムを添加した。ｃ成分は添加せず、グリセリン、および砂糖を添加した。更にその温度で攪拌混合を続け、乾燥させながら水分量を調節した。そして、その組成物を押し出し機（（株）佐藤鉄工所製）で混練および押し出しを行ない棒状石鹸を得た後、型打ち機（理研精機（株）製ＭＰ−２Ｂ型）で成形して透明石鹸を調製した。得られた透明石鹸を上記基準で評価した。表４に透明石鹸の組成と評価結果を示す。
【００５２】
【表４】

【００５３】
表４より実施例１１の透明石鹸は、溶解性が良好であり、速泡性および起泡性に優れ、非常に弾力性のある泡質を有し、洗浄時および洗いあがりの使用感が良好で、溶け崩れやひび割れを生じにくく、かつ保存安定性に優れた透明石鹸であることがわかる。
【００５４】
比較例７の透明石鹸はｂ成分を含有していないため、泡の持続率が低く、好ましい泡質が得られず、洗浄時のきしみ感が強く、保存安定性が悪い。
【００５５】
【発明の効果】
本発明の固形石鹸は、溶解性が良好であり、速泡性および起泡性に優れ、非常に弾力性のある泡質を有し、洗浄時および洗いあがりの使用感が良好で、溶け崩れやひび割れを生じにくく、かつ保存安定性に優れているので、性能および安定性の両方の点から皮膚洗浄剤として有効である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bar soap for washing skin used on the face and body. More specifically, it has good solubility, excellent quick foaming and foaming properties, has a very elastic foam quality, is excellent in terms of functions such as a feeling of use during washing and after washing, and melts. The present invention relates to a solid soap having excellent storage stability, such as being less likely to collapse or crack.
[0002]
[Prior art]
Conventionally, soaps, which are alkali metal salts of fatty acids, have been mainly used as cleansing agents for the skin of the face, body, and the like because they can provide abundant foaming and a favorable feel for use by Japanese people. Among these, solid soap is widely used as a skin cleanser because it has the advantage of foaming well in a small amount. Of course, this soap has functions such as foaming and good solubility in water, but since it is placed in a bathroom for a relatively long period of time, it does not easily melt or crack. Storage stability such as is required.
[0003]
In order to satisfy the functions and storage stability as described above, various studies have been made on the fatty acid composition of solid soap (that is, fatty acid alkali metal salt). For example, in JP-A-8-311497, JP-A-9-31497, JP-A-9-1000049, and JP-A-10-102199, saturated fatty acids and unsaturated fatty acids are used at specific ratios as fatty acids. It is described that they are used in combination. When changing the fatty acid composition of the fatty acid alkali metal salt, the content of unsaturated fatty acid is often increased in order to increase solubility in water, but only the problem of reduced function as a soap with reduced foamability In addition, there are problems in storage stability such as coloring and odor deterioration. On the other hand, in the soap with the content of unsaturated fatty acids suppressed as much as possible, the water-soluble solubility is low, so the quick foaming property is insufficient. In addition, there is a problem that it is liable to crack during storage and lacks storage stability. In addition to these, the conventional soaps mainly composed of fatty acid alkali metal salts have the problem that the foam is rough, lacks elasticity, and has a strong squeaky feeling during washing. Remaining.
[0004]
[Problems to be solved by the invention]
The object of the present invention is excellent in terms of functionality such as good solubility, excellent quick foaming and foaming properties, very elastic foam quality, and good usability during cleaning and after washing. In addition, the present invention provides a solid soap excellent in storage stability, such as being resistant to melting and cracking.
[0005]
[Means for Solving the Problems]
The present inventor has made researches to solve the above-mentioned problems, and has solved the above-mentioned problems by blending fatty acid alkali metal salt and taurine salt or N-methyl taurine salt in a specific ratio, It came to obtain the bar soap with the characteristic which is not in the past. That is, the present invention is a compound represented by the following formula (1) as an a component, 50 to 95% by weight of an alkali metal salt of a fatty acid having 8 to 22 carbon atoms, and as a b component:
[0006]
[Chemical formula 2]

[0007]
(In the formula, R represents hydrogen or a methyl group, and M represents any one of alkali metal, ammonium, and organic ammonium.) Relates to a solid soap containing 0.1 to 20% by weight.
[0008]
In a preferred embodiment, the solid soap further contains, as component c, 0.5 to 10 wt.% Of a fatty acid having 8 to 22 carbon atoms and an amino acid or an alkali metal salt of an amino acid, an ammonium salt, or an organic ammonium salt. %contains.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The fatty acid which comprises the alkali metal salt of the fatty acid which is a component has 8-22 carbon atoms. When the number of carbon atoms is 7 or less, the rapid foaming property and foaming property are lowered and the melt easily breaks down. When the number of carbon atoms is 23 or more, the rapid foaming property, foaming property and storage stability are lowered, and a good feeling of use is obtained. I can't. Examples of the fatty acid having 8 to 22 carbon atoms include caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, and a mixture of fatty acids, coconut oil fatty acid and palm kernel oil Examples include fatty acids and beef tallow fatty acids. Saturated fatty acids such as lauric acid, myristic acid, and palmitic acid are particularly preferred in terms of quick foaming properties, foaming properties, and storage stability.
[0010]
These fatty acids may be used alone or in combination of two or more. Among them, it is preferable to use a combination of lauric acid, myristic acid and palmitic acid, containing 15 to 35% by weight of lauric acid, 55 to 75% by weight of myristic acid and 5 to 20% by weight of palmitic acid, and lauric acid. Fatty acids having a total of 95 to 100% by weight of acid, myristic acid and palmitic acid are preferably used.
[0011]
Examples of the alkali metal constituting the salt with the fatty acid include sodium or potassium. Examples of the alkali agent used for preparing the alkali metal salt include metal hydroxides and metal carbonates. An alkali metal may be used independently and may be used in combination of 2 or more type. A preferable case is when potassium and sodium are used in combination, and the weight ratio of potassium / sodium is 1/4 to 3/2. More preferably, it is 1/2 to 1/3.
[0012]
The most preferable component a is a fatty acid alkali composed of lauric acid, myristic acid and palmitic acid mixed in the above specific ratio and a metal alkali agent having a potassium / sodium weight ratio of 1/4 to 3/2. It is a metal salt or a fatty acid alkali metal salt formed by combining sodium salt or potassium salt of lauric acid, myristic acid and palmitic acid in the above ratio.
[0013]
The component a is contained in an amount of 50 to 95% by weight, preferably 55 to 90% by weight. If the component a is less than 50% by weight, it tends to melt and collapse, and the quick foaming property and foaming property are reduced. When it exceeds 95% by weight, preferable foam quality and good feeling in use cannot be obtained, and solubility and storage stability are deteriorated.
[0014]
As the component b, a compound represented by the following formula (1):
[0015]
[Chemical 3]

[0016]
Is used. R represents hydrogen or a methyl group, and M is an alkali metal, ammonium, or organic ammonium. That is, when R is hydrogen, the component b is any one of an alkali metal salt, an ammonium salt, and an organic ammonium salt of taurine. When R is a methyl group, it is any of alkali metal salt, ammonium salt, and organic ammonium salt of methyl taurine. These taurine salts or methyl taurine salts may be used alone or in combination of two or more.
[0017]
Examples of the alkali metal that forms a salt with taurine or N-methyltaurine include sodium and potassium. Examples of organic ammonium include monoethanol ammonium, diethanol ammonium, and triethanol ammonium.
[0018]
The component b is contained in an amount of 0.1 to 20% by weight, preferably 0.5 to 15% by weight. However, if the component b is less than 0.1% by weight, preferable foam quality and good feeling in use cannot be obtained, and further dissolution occurs. Sexuality gets worse. When the component b exceeds 20% by weight, melting and collapse are likely to occur, and the storage stability is deteriorated.
[0019]
The solid soap of the present invention further contains, as component c, a salt of a fatty acid having 8 to 22 carbon atoms and an amino acid or an alkali metal salt, ammonium salt or organic ammonium salt of an amino acid (hereinafter sometimes referred to as a fatty acid salt). Can be contained. By adding component c, solubility and storage stability can be improved without impairing fast foaming properties, foaming properties, and foam quality. These fatty acid salts as component c may be used alone or in combination of two or more.
[0020]
The fatty acid constituting the fatty acid salt of component c has 8 to 22 carbon atoms, for example, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, and coconut which is a mixture Examples include oil fatty acids, palm kernel oil fatty acids, beef tallow fatty acids and the like. When the carbon number of the fatty acid of the component c is 7 or less, the quick foaming property and foaming property are lowered and it is easy to melt and collapse. When the carbon number is 23 or more, the fast foaming property, foaming property and storage stability are deteriorated and good. A feeling of use is not obtained.
[0021]
Examples of amino acids used to form the fatty acid salt of the component c include acidic amino acids such as aspartic acid and glutamic acid, glycine, sarcosine, alanine, β-alanine, phenylalanine, valine, oral isine, isoleucine, threonine, methionine, theanine, serine And neutral amino acids such as proline, γ-aminobutyric acid, and γ-aminocaproic acid, and basic amino acids such as arginine, ornithine, histidine, lysine, and tryptophan.
[0022]
The amino acid salt used for forming the fatty acid salt is a salt of an amino acid and an alkali metal, ammonium, or organic ammonium. Specific examples include salts of amino acids with sodium, potassium, ammonium, monoethanolammonium, diethanolammonium, and triethanolammonium. The component c is preferably contained in an amount of 0.5 to 10% by weight.
[0023]
In the solid soap of the present invention, for the purpose of further reducing the squeaky feeling during washing, α-hydroxy acids such as citric acid, tartaric acid, malic acid or salts thereof, propylene glycol, dipropylene glycol, glycerin, diglycerin, Polyhydric alcohols such as 1,3-butylene glycol and polyethylene glycol can be blended as long as the effects of the present invention are not impaired. Specifically, it is preferable to add 0.03 to 1% by weight of citric acid and 0.1 to 5% by weight of glycerin.
[0024]
Further, the bar of the present invention is a component generally blended as desired, for example, an alkyl ether sulfate type anionic surfactant, an acyl isethionate type anionic surfactant, an acyl methyl taurate type anionic interface. Anionic surfactants such as activators, amide ether sulfate type anionic surfactants, acylamino acid salt type anionic surfactants, alkyl ether carboxylate type anionic surfactants, alkylbetaine type amphoteric interfaces Activator, Amidobetaine amphoteric surfactant, Imidazolinium betaine amphoteric surfactant, Amido amino acid amphoteric surfactant, Alkylglycine amphoteric surfactant, Alkyliminodiacetic acid amphoteric surfactant, β-alkyl Aminopropionic acid type amphoteric surfactant, alkyliminodipropionic acid Amphoteric surfactants such as amphoteric surfactants, alkyldiaminoethylglycine type amphoteric surfactants, alkylsulfobetaine type amphoteric surfactants, amide sulfobetaine type amphoteric surfactants, alkylphosphobetaine type amphoteric surfactants, polyoxy Ethylene alkyl ether type nonionic surfactant, polyoxyethylene alkylphenyl ether type nonionic surfactant, polyoxyethylene fatty acid ester type nonionic surfactant, sorbitan ester type nonionic surfactant, polyoxy Ethylene sorbitan ester type nonionic surfactant, polyoxyethylene polyoxypropylene alkyl ether type nonionic surfactant, fatty acid alkanolamide type nonionic surfactant, polyoxyethylene fatty acid alkanolamide type nonionic surfactant Nonionics such as surfactants, glycerin fatty acid ester type nonionic surfactants, polyglycerin fatty acid ester type nonionic surfactants, amine oxide type nonionic surfactants, alkyl glucoside type nonionic surfactants Surfactants, higher alcohols such as cetyl alcohol and stearyl alcohol, oils such as squalane, jojoba oil, olive oil, castor oil, lanolin and lecithin, cellulose ether type cationic polymer compounds, cationic polyvinyl pyrrolidone derivatives, cation Ionic polyacrylic acid derivatives, cationic polyamide derivatives, polydimethyldiallylammonium chloride, copolymers of dimethyldiallylammonium chloride and acrylic amide, cationic polymer compounds such as alkylpolyethyleneimine, highly polymerized methylpolysiloxane Roxane, silicone derivatives such as dimethylsiloxane methyl (polyoxyethylene) siloxane copolymer, water-soluble polymers such as carboxyvinyl polymer, carboxymethylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose, paraoxybenzoic acid ester, sodium benzoate, phenoxyethanol Preservatives such as ethylenediamine tetraacetate, trisodium nitrilotriacetate, UV absorbers such as benzophenone derivatives and benzotriazole derivatives, natural extracts derived from animals and plants, other pigments, fragrances, etc. Can be included to a lesser extent.
[0025]
【Example】
The present invention will be described in terms of shells by examples.
[0026]
The preparation method, test method, and evaluation method of the bar soap in the examples will be described below.
[0027]
(Method for preparing bar soap)
Fatty acid is put into a 5 L double arm kneader (Irie Shokai Co., Ltd. PNV-5 type), heated to about 80 ° C., and mixed with a 28 wt% sodium hydroxide aqueous solution or a 28 wt% potassium hydroxide aqueous solution ( After adding an equimolar amount of Na / K (weight ratio 2/1 to 3/1) and fatty acid and stirring and mixing at 85 to 95 ° C. for about 5 minutes (preparation of component a), taurine salt as component b Or, add N-methyl taurine salt, salt of fatty acid and amino acid salt as component c, if necessary, glycerin or citric acid as other components, and continue stirring and mixing at that temperature while drying The amount of water was adjusted. The obtained composition was kneaded and extruded using an extruder (manufactured by Sato Iron Works Co., Ltd.) to obtain a bar-shaped soap, and then with a stamping machine (MP-2B model manufactured by Riken Seiki Co., Ltd.). A soap bar was prepared by molding.
[0028]
(Test method and evaluation method)
(1) was cut solubility obtained solid soaps in a rectangular bottom area 3 cm ^2. Using a soap friction solubility tester manufactured by Kuramochi Chemical Instruments Co., Ltd., the bottom of the obtained rectangular parallelepiped soap and the film conditioned with water were rubbed for 5 minutes to rotate and the weight (W1) Further, the bottom surface of the soap and the film soaked with water were rubbed for 5 minutes to measure the weight (W2), and the friction solubility was calculated by the following equation. A soap having a friction solubility of 15 or more was evaluated as a solid soap having good solubility. The water temperature was tested at 40 ° C.
Friction solubility = [(W1-W2) × 100] / 3
[0029]
In Tables 1-4, the case where the friction solubility is 15 or more is indicated by ◯, and the case where the friction solubility is less than 15 is indicated by ×.
[0030]
(2) Foaming force A soap concentration of 0 prepared by artificial hard water (prepared with calcium chloride and ion-exchanged water so as to be 100 ppm in terms of calcium carbonate) in a cup of Milcer (model number-FM-100) manufactured by Iwatani Corporation. Add 50g of 0.25wt% aqueous solution and add 0.3g of artificial dirt (consisting of 50wt% olive oil, 20wt% oleic acid, 10wt% lanolin, 10wt% liquid paraffin, 10wt% squalene) Then, the cup was covered and allowed to stand at 40 ° C. for 1 hour. After 1 hour, the cup was attached to a miller, stirred at 3000 rpm for 5 seconds, and the height of the foam 1 minute after the stirring was stopped was measured. When the height of the foam from the lowest position of the cup was 9 cm or more, it was evaluated that the foaming power was high. In Tables 1-4, the case where the height of the bubble is 9 cm or more is indicated by ◯, and the case where the height is less than 9 cm is indicated by ×.
[0031]
(3) Sustainability of foam In the measurement of foaming power in (2) above, the height of the foam after 5 minutes from the stop of stirring is measured, and when the numerical value obtained from the following formula is 90% or more, Evaluated as having high sustainability.
Duration (%) = [(bubble height after 5 minutes) / (bubble height after 1 minute)] × 100
[0032]
In Tables 1 to 4, the case where the sustain rate was 90% or more was indicated by “◯”, and the case where it was less than 90% was indicated by “X”.
[0033]
(4) Fast foaming 10 males and 10 females were used as panelists, and the foaming when the soap was foamed using a cotton towel was evaluated. 2 points when foam feels fast and feels fast foaming is good, 1 point when it feels that it takes some time until foaming, very long time until foaming, The case of feeling bad was set as 0, and the evaluation was made in the following three stages from the total score of 20 people.
○: Fast foaming property is good (total score of 30 points or more).
(Triangle | delta): A quick-foam property is a little bad (total point 20 points or more and less than 30 points).
X: Fast foaming property is poor (total score is less than 20 points).
[0034]
(5) Foam quality 10 men and women each were panelists, and the foam quality when the body was washed with solid soap was evaluated. From the total score of 20 people, 2 points when the foam feels fine and elastic, 1 point when the foam feels slightly rough, 0 when the foam feels rough and not elastic, It was evaluated in three stages.
○: The foam quality is good (total of 30 points or more).
(Triangle | delta): A foam quality is a little bad (a total point 20 points or more and less than 30 points).
X: Poor foam quality (total point less than 20 points).
[0035]
(6) Sensation of squealing at the time of washing Each panel was composed of 10 men and women, and the squeaking feeling was evaluated when the body was washed with soap and washed with hot water. Two points are given when there is no squeaky feeling, one point is given when there is a little squeaky feeling, and 0 points are given when there is a strong feeling of squeaking. did.
None: There is no squeaky feeling (total of 30 points or more).
Slightly present: Slightly squeaky (total 20 or more and less than 30).
Existence: Strong squeaky feeling (total score less than 20 points).
[0036]
(7) Sensation of skin after washing 10 men and women each as a panelist evaluated the feeling of skin after washing their body with soap. Two points were given when the skin felt completely unsatisfactory, 1 point was given when it was felt slightly tight, and 0 point was given when it was felt very tight.
None: There is no sense of tension (total score of 30 points or more).
Slightly present: There is a little feeling of tension (total score 20 points or more and less than 30 points).
Existence: Very steep (total of less than 20 points).
[0037]
(8) The melted solid soap was immersed in water at 25 ° C. for 1 hour, dried for 2 hours, and after 2 hours, the surface condition was visually observed and evaluated in the following four stages. ◎ and ○ were evaluated as solid soaps that are not easily melted (dissolve-resistant).
(Double-circle): There is almost no change with the state before a test, and it has sufficient hardness and has not melted.
○: Only the surface is soft and the inside is in a hard state, and hardly melts and collapses.
(Triangle | delta): It becomes a little soft to the inside, and has melted and collapsed a little.
X: Softened to the inside and completely melted.
[0038]
(9) Storage stability The solid soap was stored in an open system at 40 ° C. for one month, and its appearance was observed and evaluated in the following three stages.
○: Good stability (no change in appearance and odor for 1 month)
Δ: Slightly inferior (slightly colored or cracked or odor slightly deteriorated)
×: Stability failure (significant coloring and cracking or significant odor degradation)
[0039]
Examples 1-10 and Comparative Examples 1-6
Solid soaps having the compositions shown in Tables 1 to 3 were prepared and evaluated according to the above evaluation methods. The results are shown in Tables 1-3.
[0040]
[Table 1]

[0041]
[Table 2]

[0042]
[Table 3]

[0043]
From Tables 1 to 3, the bar soaps of Examples 1 to 10 of the present invention have good solubility, excellent quick foaming properties and foaming properties, have extremely elastic foam quality, and are washed. In addition, it can be seen that the soap is a solid soap that has a good feeling of use after washing, is resistant to melting and cracking, and has excellent storage stability.
[0044]
Since the content of the component a is less than 50% by weight, the solid soap of Comparative Example 1 is poor in foam height and quick foamability after 1 minute of stirring and easily melts and collapses.
[0045]
Since the content of the component a exceeds 95% by weight, the soap of Comparative Example 2 has low solubility, a preferable foam quality cannot be obtained, and a squeaky feeling during washing and a feeling of firmness of the skin after washing are strong. The storage stability is poor.
[0046]
The soap of Comparative Example 3 has a component b content of less than 0.1% by weight, so the solubility and the foam persistence are low, and the preferred foam quality cannot be obtained. There is a strong sense of tension.
[0047]
The soap of Comparative Example 4 has a component b content of more than 10% by weight, so it easily melts and has poor storage stability.
[0048]
The soap of Comparative Example 5 does not contain the component b, the foam height after 1 minute of stirring is stopped, the foam persistence is low, the preferred foam quality is not obtained, the squeaky feeling during washing is strong, and the storage stability Is bad.
[0049]
The soap bar of Comparative Example 6 does not contain the b component, has low solubility, foam retention rate, and fast foaming property, and does not provide preferable foam quality, and has a squeaky feeling during washing and a feeling of firmness after washing. Strong and poor storage stability.
[0050]
Example 11 and Comparative Example 7
A transparent soap was prepared by the following method and evaluated according to the above test method and evaluation method.
[0051]
(Method for preparing transparent soap)
Fatty acid was put into a 5 L double-arm kneader (Irie Shokai Co., Ltd., PNV-5 type), heated to about 80 ° C., and mixed with 28 wt% sodium hydroxide and potassium hydroxide (Na / K). A weight ratio of 2/1) was added in an equimolar amount with a fatty acid, and the mixture was stirred and mixed at 85 to 95 ° C. for about 5 minutes (preparation of the component a). The component c was not added, but glycerin and sugar were added. Furthermore, stirring and mixing were continued at that temperature, and the water content was adjusted while drying. The composition was kneaded and extruded with an extruder (Sato Iron Works Co., Ltd.) to obtain a bar soap, and then molded with a stamping machine (MP-2B model manufactured by Riken Seiki Co., Ltd.) to be transparent. Soap was prepared. The obtained transparent soap was evaluated according to the above criteria. Table 4 shows the composition and evaluation results of the transparent soap.
[0052]
[Table 4]

[0053]
From Table 4, the transparent soap of Example 11 has good solubility, excellent quick foaming properties and foaming properties, has a very elastic foam quality, and has a good feeling during washing and after washing. Thus, it can be seen that the transparent soap is resistant to melting and cracking and has excellent storage stability.
[0054]
Since the transparent soap of Comparative Example 7 does not contain the component b, the foam persistence is low, a favorable foam quality cannot be obtained, the squeaky feeling during washing is strong, and the storage stability is poor.
[0055]
【The invention's effect】
The soap bar of the present invention has good solubility, excellent quick foaming and foaming properties, has a very elastic foam quality, has a good feeling during washing and after washing, and melts and disintegrates Since it does not easily crack and is excellent in storage stability, it is effective as a skin cleanser from the viewpoint of both performance and stability.

Claims (2)

As the component a, 50 to 95% by weight of an alkali metal salt of a fatty acid having 8 to 22 carbon atoms, and as the component b, a compound represented by the following formula (1):

(In the formula, R represents hydrogen or a methyl group, and M represents any one of an alkali metal, ammonium, and organic ammonium). The solid soap according to claim 1, further comprising, as component c, 0.5 to 10% by weight of a fatty acid having 8 to 22 carbon atoms and an amino acid or an alkali metal salt, ammonium salt or organic ammonium salt of an amino acid. .