JP4381505B2

JP4381505B2 - Washing method

Info

Publication number: JP4381505B2
Application number: JP15962699A
Authority: JP
Inventors: 宏之西條; 修山口; 弘西村
Original assignee: Kao Corp
Current assignee: Kao Corp
Priority date: 1999-06-07
Filing date: 1999-06-07
Publication date: 2009-12-09
Anticipated expiration: 2019-06-07
Also published as: JP2000345199A

Description

【０００１】
【発明の属する技術分野】
本発明は洗濯方法に関する。
【０００２】
【従来の技術】
粒状洗剤組成物は、消費者の利便性より、高嵩密度化や低使用量化が強く指向されている。しかし、高嵩密度洗剤組成物は、該組成物を構成する洗剤粒子の溶解速度が低くなる傾向があることが知られている。また、近年の洗濯機は、環境・エネルギー問題や経済性への対応から、浴比の低下、攪拌力の低下、洗濯水の低温化、洗浄時間の短縮化等の傾向にある。これらの傾向は、いずれも洗剤粒子の溶解速度の遅延ひいては洗剤組成物の洗浄能力を著しく低下させることから、洗剤粒子の溶解速度の大幅な向上が切望されている。溶解性という点では液体洗剤は優れているが、配合上の制約から、泥汚れ、親水性色素汚れ、襟や袖口の皮脂汚れ等に対する洗浄力が粉粒状洗剤よりも劣ってしまう。
【０００３】
低攪拌力、短時間の洗浄は、衣類に優しく損傷の少ない洗濯ができ、また中浴比から低浴比（例えば浴比１０Ｌ／ｋｇ未満）の洗浄は、節水の点で有利であるが、このような条件で十分な溶解性、分散性を示す粉粒状洗剤は見出されていなかった。例えば、特表平７−５０９２６７号公報には、１５０μｍ未満の粒子１０重量％未満及び１７００μｍより大きい粒子１０重量％未満を有するベース粉末に、クエン酸ナトリウム、炭酸水素ナトリウム等の充填剤粒子を有する洗剤組成物が開示されているが、低浴比、低攪拌力、短時間の洗浄における洗剤組成物の溶解性や分散性に関する課題を十分に解決するものではなかった。
【０００４】
【発明が解決しようとする課題】
本発明の課題は、中浴比及び／又は低浴比において洗浄力に優れ、粒子溶解性及び分散性に優れる粉粒状洗剤による洗濯方法を提供することにある。
【０００５】
【課題を解決するための手段】
本発明は、水難溶性無機物と、水溶性ポリマー及び水溶性塩類から選ばれる一種以上の水溶性成分とを含有してなるベース顆粒群に、該顆粒群に対して４〜８５重量％の界面活性剤が担持されてなる洗剤粒子群を含有する粉粒状洗剤であって、１０℃における電気伝導度法による９５％溶解時間が９０秒以下の粉粒状洗剤（以下、洗剤▲１▼という）から調製される洗濯浴と洗濯物とを、浴比７〜１２Ｌ／ｋｇで用いる洗濯方法に関する。
【０００６】
また、本発明は、嵩密度５００ｇ／Ｌ以上、平均粒径１５０〜９００μｍ、且つ粒径１２５μｍ未満の粒子群の比率が１０重量％以下である洗剤粒子群を含有し、界面活性剤の含有量が４〜４０重量％である粉粒状洗剤であって、１０℃における電気伝導度法による９５％溶解時間が９０秒以下の粉粒状洗剤（以下、洗剤▲２▼という）から調製される洗濯浴と洗濯物とを、浴比７〜１２Ｌ／ｋｇで用いる洗濯方法に関する。
【０００７】
【発明の実施の形態】
洗剤▲１▼における洗剤粒子群は、ベース顆粒群に界面活性剤が担持されてなる構造である。ベース顆粒群は、１）水難溶性無機物並びに２）水溶性ポリマー及び水溶性塩類から選ばれた一種以上の水溶性成分を含有してなり、特に水溶性ポリマー及び水溶性塩類のいずれをも含有してなるベース顆粒群が、溶解性及び粒子強度の点でより好ましい。
【０００８】
ベース顆粒群の組成中、水難溶性無機物は好ましくは２０〜９０重量％、より好ましくは３０〜７５重量％である。水溶性ポリマーは好ましくは２〜３０重量％、より好ましくは３〜２０重量％である。水溶性塩類は好ましくは５〜８０重量％、より好ましくは１０〜７０重量％である。これらの範囲内であれば、ベース顆粒の構造は水溶性ポリマー及び／又は水溶性塩類がベース顆粒の内部よりも表面近傍に多く偏在した構造となる。かかるベース顆粒は、水中で表面近傍の水溶性成分が速やかに溶解して、それにより洗剤粒子表面からの洗剤粒子の崩壊を促進するという溶解挙動を示すために、高速溶解性に優れた洗剤粒子群を得ることができる。なお、ベース顆粒の構造の偏在性の確認は、例えば、フーリエ変換赤外分光法（ＦＴ−ＩＲ）や光音響分光法（ＰＡＳ）を併用する方法（ＦＴ−ＩＲ／ＰＡＳ）を用いて行うことができる。これは、ＡＰＰＬＩＥＤＳＰＥＣＴＲＯＳＣＰＯＹｖｏｌ．４７、１３１１−１３１６（１９９３）の記載に従って、ベース顆粒の表面から深さ方向における物質の分布状態を解析する方法である。
【０００９】
水難溶性無機物としては、一次粒子の平均粒径が０．１〜２０μｍのものが好ましく、結晶性又は非晶質のアルミノケイ酸塩、二酸化ケイ素、水和ケイ酸化合物、パーライト、ベントナイト等の粘土化合物等が挙げられる。中でも金属イオン封鎖能及び界面活性剤の吸油能の点で結晶性アルミノケイ酸塩が好ましい。
【００１０】
水溶性ポリマーとしては、カルボン酸系ポリマー、カルボキシメチルセルロース、可溶性澱粉、糖類等が挙げられる。中でも金属イオン封鎖能、固体汚れ・粒子汚れの分散能及び再汚染防止能の点で、分子量が数千〜１０万のカルボン酸系ポリマーが好ましい。特に、アクリル酸−マレイン酸コポリマーの塩とポリアクリル酸塩が好ましい。
【００１１】
水溶性塩類としては、炭酸塩、炭酸水素塩、硫酸塩、亜硫酸塩、硫酸水素塩、塩酸塩、又はリン酸塩等の水溶性無機塩類や、クエン酸塩やフマル酸塩等の水溶性有機酸塩が挙げられる。該水溶性塩類を配合することは、該水溶性塩類と水との反応で生じた水和熱、溶解熱により、洗剤粒子から発生する気泡を熱膨張させ、それにより粒子の崩壊性を促進できる点でより好ましい。
【００１２】
ベース顆粒群に担持させる界面活性剤としては、陰イオン界面活性剤、非イオン界面活性剤、陽イオン界面活性剤、両性界面活性剤が挙げられる。陰イオン界面活性剤としては、高級アルコールの硫酸エステル塩、高級アルコールのエトキシル化物の硫酸エステル塩、アルキルベンゼンスルホン酸塩、パラフィンスルホン酸塩、α−オレフィンスルホン酸塩、α−スルホ脂肪酸塩若しくはそのエステル塩、又は脂肪酸塩等が挙げられる。特に、炭素数が１０〜１８の、より好ましくは１２〜１４の直鎖アルキルベンゼンスルホン酸塩、炭素数が１０〜２０のα−スルホ脂肪酸アルキルエステル塩が好ましい。非イオン界面活性剤としては、高級アルコールのエチレンオキシド（以下、ＥＯという）付加物、若しくはＥＯ／プロピレンオキシド（以下、ＰＯという）付加物、脂肪酸アルカノールアミド、アルキルポリグリコシド等が挙げられる。特に炭素数が１０〜１６のアルコールのＥＯ１〜１０モル付加物が皮脂汚れの除去、耐硬水性、生分解性の点、及び直鎖アルキルベンゼンスルホン酸塩との相性の点で好ましい。両性界面活性剤としては、アルキルジメチルアミノ酢酸ベタイン、脂肪酸アミノプロピルベタイン等が、陽イオン界面活性剤としては、モノ（又はジ）長鎖アルキル型第四級アンモニウム塩等が挙げられる。ベース顆粒群に担持させる界面活性剤の量は、洗浄力の点で、ベース顆粒群に対して４〜８５重量％である。ベース顆粒群に陰イオン界面活性剤を配合させることにより、上記の偏在性を維持しつつ多量の界面活性剤を配合することができる。
【００１３】
洗剤▲１▼には、更に、衣料用洗剤の分野で公知のビルダー、漂白剤（過炭酸塩、過ホウ酸塩、漂白活性化剤等）、再汚染防止剤（カルボキシメチルセルロース等）、柔軟化剤、還元剤（亜硫酸塩等）、蛍光増白剤、抑泡剤（シリコーン等）、香料等を含有させることができる。
【００１４】
また、粒子の流動性及び非ケーキング性向上の観点から、洗剤▲１▼の洗剤粒子群と表面被覆剤とを混合して表面改質を行っても良い。表面被覆剤としては、アルミノケイ酸塩、ケイ酸カルシウム、二酸化ケイ素、ベントナイト、タルク、クレイ、非晶質シリカ誘導体、結晶性シリケート化合物等のシリケート化合物、金属石鹸、粉末の界面活性剤等の微粉体、カルボキシメチルセルロース、ポリエチレングリコール、ポリアクリル酸ソーダ、アクリル酸とマレイン酸のコポリマー又はその塩等のポリカルボン酸塩等の水溶性ポリマー、脂肪酸等が挙げられる。
【００１５】
洗剤▲１▼のＪＩＳＫ３３６２により規定された嵩密度は５００ｇ／Ｌ以上、好ましくは５００〜１０００ｇ／Ｌ、より好ましくは６００〜１０００ｇ／Ｌ、特に好ましくは６５０〜８５０ｇ／Ｌである。洗剤▲１▼の、１０℃における電気伝導度法による９５％溶解時間は９０秒以下、特に７５秒以下が好ましい。この９５％溶解時間の測定方法は次の通りである。
〔９５％溶解時間の測定方法〕
内径１０５ｍｍの円柱状の１Ｌビーカーに１０℃の蒸留水１Ｌを入れ、電気伝導度計（ＣＭ−６０Ｖ、東亜電波工業社）をセットする。全長３５ｍｍ、直径７．５ｍｍの円柱状攪拌子を用いて５５０ｒｐｍにて攪拌を行う。１０℃の試料１ｇを水の渦中心に投入する。この時点を０秒として、１０秒間隔で電気伝導度を測定する。継続して２分以上測定値が上昇しなくなった値を１００％溶解値として９５％溶解値を算出する。そしてその値に至るまでに要する時間を９５％溶解時間とする。なお、攪拌子は科学共栄社、型式ＳＡ−３５等が好適例である。
【００１６】
また、洗剤▲１▼の水分量は２０重量％以下が好ましく、１０重量％以下がより好ましく、５重量％以下が特に好ましい。
【００１７】
また、洗剤▲１▼の平均粒径は、好ましくは１５０〜９００μｍ、より好ましくは１８０〜６００μｍ、更に好ましくは１８０〜５００μｍである。洗剤▲１▼は、粒径１２５μｍ未満の粒子群の比率が全粒子群中１０重量％以下、更に８重量％以下、特に５重量％以下であることが好ましい。また、粒径７１０μｍ以上の粒子群の比率が全粒子群中１０重量％以下、更に８重量％以下、特に５重量％以下であることが好ましい。
【００１８】
また、洗剤▲１▼は、目開きが２０００μｍ、１４１０μｍ、１０００μｍ、７１０μｍ、５００μｍ、３５５μｍ、２５０μｍ、１８０μｍ及び１２５μｍの篩で篩い分けしたときの粒度分布の標準偏差を、該粒度分布の平均値で除して得られるＣＶ値が０．６以下であることが好ましく、より好ましくは０．５以下、特に好ましくは０．４以下である。このＣＶ値は、例えば、前記９段の篩を目開きが小さいものから順に受け皿の上に設置し、最上の篩に所定量の洗剤粒子群を載せて各篩を振動させる等の方法で分級した後、各篩上の残留粒子群の重量分率から測定した粒度分布を求め、各篩間の残留粒子群の対数平均と頻度（％）から粒度分布の標準偏差と平均値を算出し、標準偏差を平均値で除することにより求められる。
【００１９】
洗剤▲１▼中の洗剤粒子群の含有量は、溶解性及び洗浄性の点で５０重量％以上が好ましく、８０重量％以上がより好ましい。
【００２０】
かかる洗剤粒子群の調製には、まず、ベース顆粒群を構成する成分を含有するスラリーを調製する。次いで、スラリーを噴霧乾燥に付してベース顆粒群を得る。噴霧乾燥により、ベース顆粒群を構成する成分のうちの水溶性成分が水分の蒸発に伴ってベース顆粒表面に移動する。他にベース顆粒群は衣料用洗剤の分野で公知のビルダー、再汚染防止剤、柔軟化材、還元剤、蛍光増白剤等を含有していてもよい。次いで、得られたベース顆粒群と界面活性剤とを混合機に投入することにより、ベース顆粒群に界面活性剤を担持させることができる。
【００２１】
次に洗剤▲２▼について説明する。洗剤▲２▼は界面活性剤を、洗浄力、生産性、ケーキング防止及び流動性の観点から、４〜４０重量％、好ましくは６〜３５重量％、より好ましくは１０〜３０重量％含有する。界面活性剤は洗剤▲１▼で示した陰イオン界面活性剤、非イオン界面活性剤、両性界面活性剤、陽イオン界面活性剤等が使用できる。また、洗剤▲２▼には、洗剤▲１▼で示した水難溶性無機物、水溶性ポリマー、水溶性塩類、ビルダー、漂白剤、再汚染防止剤、柔軟化剤、還元剤、蛍光増白剤、抑泡剤、香料等を含有させることができる。
【００２２】
洗剤▲２▼に含有される洗剤粒子群の、ＪＩＳＫ３３６２により規定された嵩密度は５００ｇ／Ｌ以上、好ましくは５００〜１０００ｇ／Ｌ、より好ましくは６００〜１０００ｇ／Ｌ、特に好ましくは６５０〜８５０ｇ／Ｌである。洗剤▲２▼に含有される洗剤粒子群の平均粒径は、ペースト化による溶解遅延の防止及び洗剤粒子の溶解性の向上の点で、１５０〜９００μｍであり、１８０〜６００μｍが好ましく、１８０〜５００μｍがより好ましい。該平均粒径は洗剤▲１▼の方法で測定される。洗剤▲２▼の洗剤粒子群は、粒径１２５μｍ未満の粒子群の比率が１０重量％以下、好ましくは８重量％以下、より好ましくは５重量％以下である。また、７１０μｍ以上の粒径の粒子群の比率が１０重量％以下、更に８重量％以下、特に０重量％であることが好ましい。
【００２３】
洗剤▲２▼の、１０℃における電気伝導度法による９５％溶解時間は９０秒以下が好ましい。洗剤▲２▼の水分量は２０重量％以下が好ましく、１０重量％以下がより好ましく、５重量％以下が特に好ましい。また、洗剤▲１▼同様のＣＶ値が好ましく、更に下記の粒度分布の条件（１）又は（２）を満たすことが好ましい。
（１）粒径１８０μｍ以上５００μｍ未満の粒子群が８５重量％以上である。
（２）粒径１８０μｍ以上５００μｍ未満の粒子群が５０重量％以上８５重量％未満であり、粒径５００μｍ以上の粒子群に対する粒径１８０μｍ未満の粒子群の重量比が０．５以上、好ましくは１．０以上、より好ましくは１．５以上である。
【００２４】
洗剤▲２▼は、例えば水難溶性無機物の一部を除いた主成分を連続ニーダーを用いて捏和・混合し、得られた捏和物と残部の水難溶性無機物とを粉砕機に投入して粉砕することにより得ることができる。そして、得られた洗剤粒子群を篩い分けすることによって所定の平均粒径分布を有する洗剤粒子群を得ることができる。なお、連続ニーダーとしては、例えば、栗本鉄工所製ＫＲＣ２型、粉砕機としてはホソカワミクロン製ＤＫＡＳＯ６型等が好適例である。また、洗剤▲２▼は、洗剤粒子群となる成分を含有する水性スラリーを噴霧乾燥し、次いで噴霧乾燥粒子をスクリュー押し出し造粒機等で造粒して得た造粒粒子群を、ロータリーキルン等でゼオライト、酵素、結晶性シリケート等と混合し、必要に応じて香料をスプレーする方法により得た洗剤粒子群を、分級器で粒度分布を調整することにより得ることができる。
【００２５】
本発明の洗濯方法は、上記の洗剤▲１▼又は▲２▼から調製される洗濯浴と洗濯物との浴比７〜１２Ｌ／ｋｇとして行う。浴比は、洗濯物１ｋｇ当たりの洗濯浴の水量（Ｌ）である。洗浄時間は、２〜３０分、特に３〜２０分が好ましい。該洗濯浴の温度は３〜６０℃、特に５〜４０℃が好ましい。該洗濯浴中の粉粒状洗剤濃度は、全界面活性剤の濃度として０．０１〜０．５重量％、特に０．０１〜０．１重量％が好ましい。本発明の洗濯方法は洗濯機を用いることが好ましいが、手洗いにより行うこともできる。
【００２６】
【発明の効果】
本発明によれば、低浴比の洗浄においても優れた洗浄力が得られる洗濯方法が提供される。
【００２７】
【実施例】
＜製造例１＞
攪拌翼を有する混合槽に水を加え、水温が５５℃に達した後に、４０重量％濃度のアクリル酸−マレイン酸コポリマー水溶液を添加した。これを１５分間攪拌した後に、炭酸ナトリウム、硫酸ナトリウム、亜硫酸ナトリウム、蛍光染料を添加した。更に１５分間攪拌した後に、ゼオライトを添加した。これを３０分間攪拌してスラリーを得た（スラリーの最終温度は６０℃）。このスラリーを噴霧乾燥塔に供給し、噴霧圧力２５ｋｇ／ｃｍ²で塔頂より噴霧を行うことによりベース顆粒群を調製した。得られたベース顆粒群の組成は、アクリル酸−マレイン酸コポリマー６重量％、炭酸ナトリウム２６重量％、硫酸ナトリウム１０重量％、亜硫酸ナトリウム１．５重量％、蛍光染料０．５重量％、ゼオライト５２重量％、水４重量％であった。なお、アクリル酸−マレイン酸コポリマーはナトリウム塩（７０モル％中和）であり、モノマー比はアクリル酸／マレイン酸＝３／７（モル比）であった。蛍光染料はチノパールＣＢＳ−ＸとチノパールＡＭＳ−ＧＸ（何れもチバガイギー社）とを１／１の重量比で混合したものを用いた。ゼオライトは４Ａ型ゼオライト（東ソー社）を用いた。
【００２８】
次いで、ベース顆粒群に界面活性剤等を添加することにより洗剤粒子群を得た。即ち、まず非イオン界面活性剤、陰イオン界面活性剤酸前駆体、ポリエチレングリコール、及びアルカリ水溶液を加熱混合して７０℃の活性剤混合液を得た。活性剤混合液の組成は、非イオン界面活性剤１５重量部、陰イオン界面活性剤１５重量部、ポリエチレングリコール１重量部、水８重量部であった。なお、非イオン界面活性剤は、アルキル基炭素数１２〜１６、平均ＥＯ付加モル数６．０のポリオキシエチレンアルキルエーテルを用いた。陰イオン界面活性剤はドデシルベンゼンスルホン酸ナトリウムを用いた。ポリエチレングリコールは平均分子量８５００のものを用いた。次に、レディゲミキサー（松阪技研社、容量２０Ｌ、ジャケット付き）に上記ベース顆粒群１００重量部を投入し、主軸（１５０ｒｐｍ）の攪拌を開始した。そこに、上記活性剤混合液を３分間で投入し、その後５分間攪拌を行い、洗剤粒子群を得た。更に、このミキサーに結晶性シリケート１０重量部と非晶質アルミノケイ酸塩６重量部とを投入し、洗剤粒子群の表面被覆を行った。なお、結晶性シリケートは粉末ＳＫＳ−６（クラリアントトクヤマ社）を用いた。非晶質アルミノケイ酸塩は、Ａｌ₂Ｏ₃＝２９．６重量％、ＳｉＯ₂＝５２．４重量％、Ｎａ₂Ｏ＝１８．０重量％（１．０Ｎａ₂Ｏ・Ａｌ₂Ｏ₃・３．１ＳｉＯ₂）の組成のもの（原子吸光分析及びプラズマ発行分析による）を用いた。また、その吸油能は２８５ｍＬ／１００ｇ、含水分量は１１．２重量％であった。
【００２９】
次いで、目開き２０００μｍの篩を用いて洗剤粒子群を分級し、２０００μｍ未満の粒径の洗剤粒子群を得た。得られた洗剤粒子群１００重量部に酵素１．５重量部と香料０．５重量部を混合して粉粒状洗剤を得た。なお、酵素はセルラーゼＫ（特開昭６３−２６４６９９号公報記載）とリポラーゼ１００Ｔ（ノボ社製）を１：１の重量比で混合したものを用いた。分級器で分級し、表２に表す粒度分布に調整した。また、９５％溶解時間を表２に示す。
【００３０】
＜製造例２＞
次の方法で表１の配合例の洗剤粒子群を製造した。表１中のゼオライトの５重量％分、酵素、香料、及び結晶性シリケート以外の成分で含水率５０％の水性スラリーを調整し、噴霧乾燥を行う。次いでスクリュー押し出し造粒機により造粒し、洗剤粒子群を得る。これをロータリーキルンに入れ、ゼオライト５重量％、酵素、結晶性シリケートをブレンドし、同時に香料をスプレーし最終洗剤粒子群を得た。分級器で分級し、表２に表した粒度分布の洗剤粒子群からなる粉粒状洗剤を調製した。また、９５％溶解時間を表２に示す。
【００３１】
【表１】

【００３２】
＊１：チノパールＣＢＳ−ＸとチノパールＡＭＳ−ＧＸ（何れもチバガイギー社とを２／１の重量比で混合したもの。
【００３３】
【表２】

【００３４】
＜比較洗剤１：高嵩密度粒状洗剤＞
直鎖アルキル（炭素数１０〜１３）ベンゼンスルホン酸カリウム１４部、α−スルホ脂肪酸（炭素数１４〜１６）メチルエステルナトリウム８部、製造例１と同じ非イオン界面活性剤１部、石鹸（炭素数１４〜２０）７部、４Ａ型ゼオライト１０部、１号珪酸ナトリウム１部、炭酸ナトリウム５部、炭酸カリウム１６部、芒硝１．１部、亜硫酸ナトリウム１．５部、ポリアクリル酸ナトリウム（平均分子量１万）２部、製造例１と同じポリエチレングリコール２部、蛍光染料〔チノパールＣＢＳ−Ｘ（チバガイギー社）０．２部、ホワイテックスＳＡ（住友化学社）０．１部〕を水と混合して固形分４８重量％のスラリーを調製した（温度６５℃）。これを向流式噴霧乾燥装置を用いて嵩密度約３２０ｇ／Ｌの粒子を得た。揮発分（１０５℃、２時間の減量）は３％であった。次に、上記粒子５０ｋｇ／Ｈ、炭酸ナトリウム（重灰）４ｋｇ／Ｈ、製造例１と同じ結晶性シリケート粉末１ｋｇ／Ｈ、上記非イオン界面活性剤３ｋｇ／Ｈの能力で連続ニーダー（栗本鉄工所（株））に連続的に添加した。ニーダー排出口に２軸式押出し機（ペレッターダブル：不二パウダル社）を設置して、直径約３ｍｍの円柱状ペレットを得た。このペレット１００部に対して、解砕助剤として粉末ゼオライト（平均粒径約３μｍ）５部を加えつつ、１４℃の冷風を通気しながら目開き１．５ｍｍのスクリーンを取り付けたフィッツミル（ホソカワミクロン社）により解砕造粒を行った。得られた粒状洗剤は、嵩密度７９１ｇ／Ｌ、平均粒径６０５μｍ、粒径７１０μｍ以上の粒子群の比率３７．４％、１２５μｍ未満の粒子群の比率３．８％、９５％溶解時間１０２秒であった。
【００３５】
＜比較洗剤２：液体洗剤＞
フルパワーボーナス（プロクターアンドギャンブル社）Ｌｏｔ．Ｎｏ．８２８７ＡＢ。
【００３６】
実施例
浴比１１Ｌ／ｋｇで１０℃、５分間の洗浄試験を行ったところ、製造法１及び２の粉粒状洗剤は、何れも比較洗剤１、２よりも洗浄力に勝っていた。比較洗剤１は布に粉残留が認められた。洗浄試験の条件は、上記の他は、特開平１０−１６８４８５号公報の第１４欄第６行以降に記載の方法に従った。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a washing method.
[0002]
[Prior art]
The granular detergent composition is strongly directed to increase the bulk density and reduce the amount of use for the convenience of consumers. However, it is known that a high bulk density detergent composition tends to have a low dissolution rate of detergent particles constituting the composition. In recent years, washing machines tend to have a reduced bath ratio, a reduced stirring power, a lower temperature for washing water, and a shorter washing time in order to cope with environmental and energy problems and economy. Since all of these tendencies cause a delay in the dissolution rate of the detergent particles and thus the cleaning ability of the detergent composition, it is desired to greatly improve the dissolution rate of the detergent particles. Liquid detergents are superior in terms of solubility, but due to compounding restrictions, the cleaning power against mud stains, hydrophilic pigment stains, sebum stains on collars and cuffs, etc. is inferior to granular detergents.
[0003]
Low stirring force and short-time washing can wash clothes with little damage, and washing from a medium bath ratio to a low bath ratio (for example, less than 10 L / kg bath ratio) is advantageous in terms of water saving. A granular detergent exhibiting sufficient solubility and dispersibility under such conditions has not been found. For example, Japanese Patent Publication No. 7-509267 has filler particles such as sodium citrate and sodium bicarbonate in a base powder having less than 10% by weight of particles less than 150 μm and less than 10% by weight of particles greater than 1700 μm. Although a detergent composition has been disclosed, it has not sufficiently solved the problems relating to the solubility and dispersibility of the detergent composition in a low bath ratio, a low stirring force, and a short cleaning time.
[0004]
[Problems to be solved by the invention]
The subject of this invention is providing the washing | cleaning method by the granular detergent which is excellent in detergency in medium bath ratio and / or low bath ratio, and is excellent in particle solubility and dispersibility.
[0005]
[Means for Solving the Problems]
The present invention provides a base granule group comprising a hardly water-soluble inorganic substance and one or more water-soluble components selected from water-soluble polymers and water-soluble salts, and has a surface activity of 4 to 85% by weight based on the granule group. A granular detergent containing a group of detergent particles on which an agent is supported, prepared from a granular detergent (hereinafter referred to as detergent (1)) having a 95% dissolution time of 90 seconds or less by an electric conductivity method at 10 ° C. The present invention relates to a washing method in which a washing bath and laundry are used at a bath ratio of 7 to 12 L / kg.
[0006]
The present invention also includes a detergent particle group having a bulk density of 500 g / L or more, an average particle diameter of 150 to 900 μm, and a ratio of the particle group of less than 125 μm of 10% by weight or less, and the surfactant content. Washing bath prepared from a granular detergent having a 95% dissolution time of 90 seconds or less by electric conductivity method at 10 ° C. (hereinafter referred to as detergent (2)) The present invention relates to a laundry method in which a laundry is used at a bath ratio of 7 to 12 L / kg.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
The detergent particle group in the detergent (1) has a structure in which a surfactant is supported on the base granule group. The base granule group contains one or more water-soluble components selected from 1) poorly water-soluble inorganic substances and 2) water-soluble polymers and water-soluble salts, and particularly contains both water-soluble polymers and water-soluble salts. The base granule group is more preferable in terms of solubility and particle strength.
[0008]
In the composition of the base granule group, the hardly water-soluble inorganic substance is preferably 20 to 90% by weight, more preferably 30 to 75% by weight. The water-soluble polymer is preferably 2 to 30% by weight, more preferably 3 to 20% by weight. The water-soluble salt is preferably 5 to 80% by weight, more preferably 10 to 70% by weight. Within these ranges, the structure of the base granule becomes a structure in which water-soluble polymers and / or water-soluble salts are more unevenly distributed near the surface than inside the base granule. This base granule has a dissolution behavior in which water-soluble components in the vicinity of the surface dissolve quickly in water, thereby accelerating the disintegration of the detergent particles from the surface of the detergent particles. A group can be obtained. In addition, confirmation of the uneven distribution of the structure of the base granule is performed using, for example, a method (FT-IR / PAS) that uses Fourier transform infrared spectroscopy (FT-IR) or photoacoustic spectroscopy (PAS) in combination. Can do. This is an APPLIED SPECTROSPOY vol. 47, 1311-1316 (1993), a method for analyzing the distribution state of a substance in the depth direction from the surface of the base granule.
[0009]
As the poorly water-soluble inorganic substance, those having an average primary particle size of 0.1 to 20 μm are preferable, and a clay compound such as crystalline or amorphous aluminosilicate, silicon dioxide, hydrated silicate compound, perlite, bentonite, etc. Etc. Of these, crystalline aluminosilicate is preferable in terms of sequestering ability and surfactant oil absorption ability.
[0010]
Examples of the water-soluble polymer include carboxylic acid polymers, carboxymethyl cellulose, soluble starch, saccharides and the like. Among them, a carboxylic acid polymer having a molecular weight of several thousand to 100,000 is preferable in terms of sequestering ability, dispersibility of solid dirt / particle dirt, and ability to prevent recontamination. Particularly preferred are salts of acrylic acid-maleic acid copolymers and polyacrylates.
[0011]
Water-soluble salts include water-soluble inorganic salts such as carbonates, hydrogen carbonates, sulfates, sulfites, hydrogen sulfates, hydrochlorides, and phosphates, and water-soluble organics such as citrates and fumarates. Acid salts. By blending the water-soluble salts, the bubbles generated from the detergent particles are thermally expanded by the heat of hydration and the heat of dissolution generated by the reaction of the water-soluble salts and water, thereby promoting the disintegration of the particles. More preferable in terms.
[0012]
Examples of the surfactant to be supported on the base granule group include an anionic surfactant, a nonionic surfactant, a cationic surfactant, and an amphoteric surfactant. Anionic surfactants include higher alcohol sulfates, higher alcohol ethoxylate sulfates, alkylbenzene sulfonates, paraffin sulfonates, α-olefin sulfonates, α-sulfo fatty acid salts or esters thereof. Examples thereof include salts or fatty acid salts. Particularly preferred are linear alkylbenzene sulfonates having 10 to 18 carbon atoms, more preferably 12 to 14 carbon atoms, and α-sulfo fatty acid alkyl ester salts having 10 to 20 carbon atoms. Examples of the nonionic surfactant include ethylene oxide (hereinafter referred to as EO) adducts of higher alcohols or EO / propylene oxide (hereinafter referred to as PO) adducts, fatty acid alkanolamides, alkyl polyglycosides, and the like. In particular, an EO 1 to 10 mol adduct of an alcohol having 10 to 16 carbon atoms is preferable in terms of removal of sebum soil, hard water resistance, biodegradability, and compatibility with linear alkylbenzene sulfonate. Examples of amphoteric surfactants include alkyldimethylaminoacetic acid betaines and fatty acid aminopropyl betaines, and examples of cationic surfactants include mono (or di) long chain alkyl quaternary ammonium salts. The amount of the surfactant to be supported on the base granule group is 4 to 85% by weight with respect to the base granule group in terms of detergency. By incorporating an anionic surfactant into the base granule group, a large amount of the surfactant can be blended while maintaining the uneven distribution.
[0013]
Detergent (1) includes builder, bleach (percarbonate, perborate, bleach activator, etc.), recontamination inhibitor (carboxymethylcellulose, etc.), softening Agents, reducing agents (sulfites, etc.), fluorescent brighteners, foam inhibitors (silicones, etc.), fragrances, and the like can be included.
[0014]
Further, from the viewpoint of improving the fluidity and non-caking property of the particles, the surface modification may be performed by mixing the detergent particles of the detergent (1) and the surface coating agent. As surface coating agent, fine powder such as aluminosilicate, calcium silicate, silicon dioxide, bentonite, talc, clay, amorphous silica derivative, crystalline silicate compound such as silicate compound, metal soap, powder surfactant , Carboxymethyl cellulose, polyethylene glycol, sodium polyacrylate, water-soluble polymers such as polycarboxylic acid salts such as copolymers of acrylic acid and maleic acid or salts thereof, fatty acids, and the like.
[0015]
The bulk density defined by JIS K 3362 of the detergent (1) is 500 g / L or more, preferably 500 to 1000 g / L, more preferably 600 to 1000 g / L, and particularly preferably 650 to 850 g / L. Detergent (1) has a 95% dissolution time of 10 seconds or less at 10 ° C. of 90 seconds or less, particularly preferably 75 seconds or less. The method for measuring the 95% dissolution time is as follows.
[Measurement method of 95% dissolution time]
Into a cylindrical 1 L beaker with an inner diameter of 105 mm, 1 L of distilled water at 10 ° C. is placed, and an electric conductivity meter (CM-60V, Toa Denpa Kogyo Co., Ltd.) is set. Stirring is performed at 550 rpm using a cylindrical stirring bar having a total length of 35 mm and a diameter of 7.5 mm. 1 g of a sample at 10 ° C. is put into the vortex center of water. The electrical conductivity is measured at 10 second intervals with this time as 0 second. The 95% dissolution value is calculated by taking the value at which the measured value does not increase continuously for 2 minutes or more as the 100% dissolution value. The time required to reach this value is taken as 95% dissolution time. A suitable example of the stirrer is Science Kyoeisha, model SA-35, and the like.
[0016]
The water content of the detergent (1) is preferably 20% by weight or less, more preferably 10% by weight or less, and particularly preferably 5% by weight or less.
[0017]
The average particle size of the detergent (1) is preferably 150 to 900 μm, more preferably 180 to 600 μm, and still more preferably 180 to 500 μm. In the detergent (1), the ratio of the particle group having a particle size of less than 125 μm is preferably 10% by weight or less, more preferably 8% by weight or less, and particularly preferably 5% by weight or less in the total particle group. Further, the ratio of particle groups having a particle size of 710 μm or more is preferably 10% by weight or less, more preferably 8% by weight or less, and particularly preferably 5% by weight or less in the total particle group.
[0018]
In addition, for detergent (1), the standard deviation of the particle size distribution when sieved with sieves of 2000 μm, 1410 μm, 1000 μm, 710 μm, 500 μm, 355 μm, 250 μm, 180 μm and 125 μm is the average value of the particle size distribution. The CV value obtained by dividing is preferably 0.6 or less, more preferably 0.5 or less, and particularly preferably 0.4 or less. The CV value is classified by, for example, a method in which the 9-stage sieve is placed on a tray in order from the smallest opening, and a predetermined amount of detergent particles are placed on the top sieve and each sieve is vibrated. After that, obtain the particle size distribution measured from the weight fraction of the residual particle group on each sieve, calculate the standard deviation and the average value of the particle size distribution from the logarithmic average and frequency (%) of the residual particle group between each sieve, It is obtained by dividing the standard deviation by the average value.
[0019]
The content of the detergent particles in the detergent (1) is preferably 50% by weight or more, and more preferably 80% by weight or more in terms of solubility and detergency.
[0020]
For the preparation of such detergent particles, first, a slurry containing the components constituting the base granules is prepared. The slurry is then subjected to spray drying to obtain a base granule group. By spray drying, the water-soluble component of the components constituting the base granule group moves to the base granule surface with the evaporation of moisture. In addition, the base granule group may contain a builder, an anti-staining agent, a softening material, a reducing agent, a fluorescent whitening agent, and the like known in the field of garment detergents. Next, the obtained base granule group and the surfactant are put into a mixer, whereby the surfactant can be supported on the base granule group.
[0021]
Next, the detergent (2) will be described. The detergent (2) contains a surfactant in an amount of 4 to 40% by weight, preferably 6 to 35% by weight, more preferably 10 to 30% by weight, from the viewpoint of detergency, productivity, caking prevention and fluidity. As the surfactant, anionic surfactants, nonionic surfactants, amphoteric surfactants, cationic surfactants and the like shown in detergent (1) can be used. In addition, the detergent (2) includes the poorly water-soluble inorganic substances, water-soluble polymers, water-soluble salts, builders, bleaching agents, anti-staining agents, softening agents, reducing agents, fluorescent whitening agents, A foam suppressant, a fragrance | flavor, etc. can be contained.
[0022]
The bulk density defined by JIS K 3362 of the detergent particles contained in the detergent (2) is 500 g / L or more, preferably 500 to 1000 g / L, more preferably 600 to 1000 g / L, and particularly preferably 650. 850 g / L. The average particle diameter of the detergent particle group contained in the detergent (2) is 150 to 900 μm, preferably 180 to 600 μm, preferably 180 to 600 μm from the viewpoint of preventing dissolution delay due to pasting and improving the solubility of the detergent particles. 500 μm is more preferable. The average particle diameter is measured by the method of detergent (1). In the detergent particle group of the detergent (2), the ratio of the particle group having a particle size of less than 125 μm is 10% by weight or less, preferably 8% by weight or less, more preferably 5% by weight or less. The ratio of the particle group having a particle diameter of 710 μm or more is preferably 10% by weight or less, more preferably 8% by weight or less, and particularly preferably 0% by weight.
[0023]
The 95% dissolution time of the detergent (2) by the electric conductivity method at 10 ° C. is preferably 90 seconds or less. The water content of the detergent (2) is preferably 20% by weight or less, more preferably 10% by weight or less, and particularly preferably 5% by weight or less. Further, the CV value similar to that of the detergent (1) is preferable, and it is preferable that the following condition (1) or (2) of the particle size distribution is satisfied.
(1) A particle group having a particle size of 180 μm or more and less than 500 μm is 85% by weight or more.
(2) The particle group having a particle size of 180 μm or more and less than 500 μm is 50% by weight or more and less than 85% by weight, and the weight ratio of the particle group having a particle size of less than 180 μm to the particle group having a particle size of 500 μm or more is preferably 0.5 or more, 1.0 or more, more preferably 1.5 or more.
[0024]
For detergent (2), for example, the main component excluding a part of the hardly water-soluble inorganic substance is kneaded and mixed using a continuous kneader, and the obtained kneaded substance and the remaining hardly water-soluble inorganic substance are put into a grinder. It can be obtained by grinding. And the detergent particle group which has a predetermined | prescribed average particle size distribution can be obtained by sieving the obtained detergent particle group. Suitable examples of the continuous kneader include KRC type 2 manufactured by Kurimoto Iron Works, and DKASO type 6 manufactured by Hosokawa Micron as the crusher. In addition, the detergent (2) is a granulated particle group obtained by spray drying an aqueous slurry containing a component that becomes a detergent particle group, and then granulating the spray dried particle by a screw extrusion granulator or the like. The detergent particles obtained by mixing with zeolite, enzyme, crystalline silicate and the like, and spraying the fragrance as necessary can be obtained by adjusting the particle size distribution with a classifier.
[0025]
The washing method of the present invention is carried out at a bath ratio of 7 to 12 L / kg between the washing bath prepared from the detergent (1) or (2) and the laundry. The bath ratio is the amount of water (L) of the washing bath per 1 kg of the laundry. The washing time is preferably 2 to 30 minutes, particularly 3 to 20 minutes. The temperature of the washing bath is preferably 3 to 60 ° C, particularly preferably 5 to 40 ° C. The concentration of the granular detergent in the washing bath is preferably 0.01 to 0.5% by weight, particularly 0.01 to 0.1% by weight as the total surfactant concentration. The washing method of the present invention preferably uses a washing machine, but can also be performed by hand washing.
[0026]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the washing | cleaning method in which the outstanding cleaning power is acquired also in washing | cleaning of a low bath ratio is provided.
[0027]
【Example】
<Production Example 1>
Water was added to a mixing tank having a stirring blade, and after the water temperature reached 55 ° C., an aqueous acrylic acid-maleic acid copolymer solution having a concentration of 40% by weight was added. After stirring for 15 minutes, sodium carbonate, sodium sulfate, sodium sulfite, and fluorescent dye were added. After stirring for an additional 15 minutes, the zeolite was added. This was stirred for 30 minutes to obtain a slurry (the final temperature of the slurry was 60 ° C.). This slurry was supplied to a spray drying tower, and sprayed from the top of the tower at a spraying pressure of 25 kg / cm ² to prepare a base granule group. The composition of the obtained base granule group was as follows: acrylic acid-maleic acid copolymer 6% by weight, sodium carbonate 26% by weight, sodium sulfate 10% by weight, sodium sulfite 1.5% by weight, fluorescent dye 0.5% by weight, zeolite 52 % By weight and 4% by weight of water. The acrylic acid-maleic acid copolymer was a sodium salt (70 mol% neutralized), and the monomer ratio was acrylic acid / maleic acid = 3/7 (molar ratio). The fluorescent dye used was a mixture of Chinopearl CBS-X and Chinopearl AMS-GX (both Ciba Geigy) at a weight ratio of 1/1. As zeolite, 4A-type zeolite (Tosoh Corporation) was used.
[0028]
Next, detergent particles were obtained by adding a surfactant or the like to the base granules. That is, first, a nonionic surfactant, an anionic surfactant acid precursor, polyethylene glycol, and an alkaline aqueous solution were heated and mixed to obtain an activator mixture at 70 ° C. The composition of the surfactant mixed solution was 15 parts by weight of a nonionic surfactant, 15 parts by weight of an anionic surfactant, 1 part by weight of polyethylene glycol, and 8 parts by weight of water. As the nonionic surfactant, polyoxyethylene alkyl ether having an alkyl group having 12 to 16 carbon atoms and an average EO addition mole number of 6.0 was used. As the anionic surfactant, sodium dodecylbenzenesulfonate was used. Polyethylene glycol having an average molecular weight of 8500 was used. Next, 100 parts by weight of the base granule group was put into a Redige mixer (Matsusaka Giken Co., Ltd., capacity 20 L, with jacket), and stirring of the main shaft (150 rpm) was started. The said active agent liquid mixture was thrown in in 3 minutes there, and it stirred for 5 minutes after that, and obtained the detergent particle group. Furthermore, 10 parts by weight of crystalline silicate and 6 parts by weight of amorphous aluminosilicate were added to this mixer to coat the surface of the detergent particles. As the crystalline silicate, powder SKS-6 (Clariant Tokuyama) was used. Amorphous aluminosilicates, Al ₂ O ₃ = 29.6 wt%, SiO ₂ = 52.4 wt%, Na ₂ O = 18.0 _{_{wt% (1.0Na 2 O · Al 2}} O 3 · 3 .1SiO ₂ ) (by atomic absorption analysis and plasma emission analysis). The oil absorption capacity was 285 mL / 100 g, and the water content was 11.2% by weight.
[0029]
Next, the detergent particles were classified using a sieve having an opening of 2000 μm to obtain detergent particles having a particle diameter of less than 2000 μm. A granular detergent was obtained by mixing 100 parts by weight of the obtained detergent particle group with 1.5 parts by weight of enzyme and 0.5 parts by weight of fragrance. The enzyme used was a mixture of cellulase K (described in JP-A 63-264699) and lipolase 100T (manufactured by Novo) at a weight ratio of 1: 1. Classification was performed with a classifier, and the particle size distribution shown in Table 2 was adjusted. The 95% dissolution time is shown in Table 2.
[0030]
<Production Example 2>
The detergent particle group of the formulation example of Table 1 was manufactured with the following method. An aqueous slurry having a water content of 50% is prepared with components other than 5% by weight of zeolite in Table 1, enzymes, fragrances, and crystalline silicate, and spray drying is performed. Next, granulation is performed by a screw extrusion granulator to obtain a detergent particle group. This was put into a rotary kiln, 5 wt% zeolite, enzyme, and crystalline silicate were blended, and at the same time, a fragrance was sprayed to obtain a final detergent particle group. After classifying with a classifier, a granular detergent consisting of detergent particle groups having the particle size distribution shown in Table 2 was prepared. The 95% dissolution time is shown in Table 2.
[0031]
[Table 1]

[0032]
* 1: Chino Pearl CBS-X and Chino Pearl AMS-GX (both mixed with Ciba Geigy in a weight ratio of 2/1).
[0033]
[Table 2]

[0034]
<Comparative detergent 1: High bulk density granular detergent>
Linear alkyl (carbon number 10-13) benzene sulfonate potassium 14 parts, α-sulfo fatty acid (carbon number 14-16) methyl ester sodium 8 parts, the same nonionic surfactant 1 part as in Production Example 1, soap (carbon 14 to 20) 7 parts, 10 parts of 4A zeolite, 1 part of 1 sodium silicate, 5 parts of sodium carbonate, 16 parts of potassium carbonate, 1.1 parts of sodium sulfate, 1.5 parts of sodium sulfite, sodium polyacrylate (average) 2 parts of molecular weight 10,000), 2 parts of the same polyethylene glycol as in Production Example 1, 0.2 parts of fluorescent dye [Chinopearl CBS-X (Ciba Geigy), 0.1 part of Whiteex SA (Sumitomo Chemical)] mixed with water Thus, a slurry having a solid content of 48% by weight was prepared (temperature: 65 ° C.). Using a counter-current spray drying apparatus, particles having a bulk density of about 320 g / L were obtained. Volatiles (105 ° C., 2 hours loss) were 3%. Next, a continuous kneader (Kurimoto Iron Works) with the capacity of 50 kg / H of the particles, 4 kg / H of sodium carbonate (heavy ash), 1 kg / H of the same crystalline silicate powder as in Production Example 1, and 3 kg / H of the nonionic surfactant. Added continuously). A twin-screw extruder (Pelleter Double: Fuji Powder Co., Ltd.) was installed at the kneader discharge port to obtain a cylindrical pellet having a diameter of about 3 mm. Fitzmill (Hosokawa Micron) fitted with a screen having a mesh opening of 1.5 mm while adding cold zeolite at 14 ° C. while adding 5 parts of powdered zeolite (average particle size of about 3 μm) as a crushing aid to 100 parts of the pellets. Crushing and granulation. The obtained granular detergent has a bulk density of 791 g / L, an average particle diameter of 605 μm, a ratio of particle groups having a particle diameter of 710 μm or more, 37.4%, a ratio of particle groups of less than 125 μm, 3.8%, a 95% dissolution time of 102 seconds. Met.
[0035]
<Comparative detergent 2: Liquid detergent>
Full Power Bonus (Procter & Gamble Company) Lot. No. 8287AB.
[0036]
When a washing test was carried out at 10 ° C. for 5 minutes at an example bath ratio of 11 L / kg, the granular detergents of production methods 1 and 2 were superior to the cleaning detergents 1 and 2, respectively. In Comparative detergent 1, powder residue was found on the cloth. The conditions of the cleaning test were in accordance with the method described in JP-A-10-168485, column 14, line 6 and subsequent lines, except for the above.

Claims

The base granule group containing 20 to 90% by weight of a poorly water-soluble inorganic substance, 2 to 30% by weight of a water-soluble polymer and 5 to 70% by weight of a water-soluble salt and substantially free of a surfactant, It is a granular detergent containing a detergent particle group on which a surfactant containing at least 4 to 85% by weight of an anionic surfactant is supported, and 95% dissolution time by an electric conductivity method at 10 ° C Is a washing method using a washing bath and laundry prepared from a granular detergent having a bathing time of 90 seconds or less at a bath ratio of 7 to 12 L / kg.

The granular detergent contains a linear alkylbenzene sulfonate having 10 to 18 carbon atoms and / or an α-sulfo fatty acid alkyl ester salt having 10 to 20 carbon atoms as a surfactant carried on the base granules. The washing method according to claim 1.

The washing method according to claim 1 or 2, wherein the base granule group has a structure in which a water-soluble polymer and / or a water-soluble salt is more unevenly distributed near the surface than inside.

The washing method according to any one of claims 1 to 3, wherein the granular detergent contains 8 to 50% by weight of an alkali agent and / or a calcium scavenger.

The washing method according to any one of claims 1 to 4, wherein the granular detergent contains, as a surfactant, an adduct of 1 to 10 moles of ethylene oxide of an alcohol having 10 to 16 carbon atoms.

The base granule group containing 20 to 90% by weight of a poorly water-soluble inorganic substance, 2 to 30% by weight of a water-soluble polymer and 5 to 70% by weight of a water-soluble salt and substantially free of a surfactant, It is a granular detergent containing a detergent particle group on which a surfactant containing at least 4 to 85% by weight of an anionic surfactant is supported, and 95% dissolution time by an electric conductivity method at 10 ° C Is a granular detergent used in a washing method having a bath ratio of 7 to 12 L / kg.

The surfactant according to claim 6, comprising a linear alkylbenzene sulfonate having 10 to 18 carbon atoms and / or an α-sulfo fatty acid alkyl ester salt having 10 to 20 carbon atoms as a surfactant supported on the base granule group. Powder detergent.

The granular detergent according to claim 6 or 7, wherein the base granule group has a structure in which water-soluble polymers and / or water-soluble salts are more unevenly distributed near the surface than inside.