JP4213429B2

JP4213429B2 - Screening method of inorganic powder composition effective for eliminating dull skin, inorganic powder composition thereof, and cosmetics using the composition

Info

Publication number: JP4213429B2
Application number: JP2002235012A
Authority: JP
Inventors: 明大岡田; 保森; 太郎大西; 博和田中; 巧宮崎
Original assignee: JGC Catalysts and Chemicals Ltd; Naris Cosmetics Co Ltd
Current assignee: JGC Catalysts and Chemicals Ltd; Naris Cosmetics Co Ltd
Priority date: 2002-08-12
Filing date: 2002-08-12
Publication date: 2009-01-21
Anticipated expiration: 2022-08-12
Also published as: JP2004073327A

Description

【０００１】
【発明の属する技術分野】
本発明は、皮膚くすみの解消に有効な無機粉体組成物のスクリーニング法、並びに該スクリーニング法により選択された無機粉体組成物及びその組成物を含有する化粧料に関するものである。
【０００２】
【従来の技術】
皮膚（肌）のくすみに関して、日本化粧品工業連合会編集、１９９５、１０１、日本化粧品工業連合会技術資料、ｐ１４８によると「くすみとはある特定の視覚現象である。顔全体または目のまわりや頬などの部位に生じ、肌の赤みが減少して黄みが増し、および／または肌のつやや透明感が減少したり、皮膚の表面の凹凸などによる影によって明度が低下してみえる状態で、境界線は不明瞭である。」と、多様で総合的な視覚的現象として定義されている。
【０００３】
計測機器を用いたくすみの測定項目として、１）肌色の明度または色相、２）肌色の不均一性、３）皮膚の凹凸、４）光の透過度、５）光沢値、を挙げている。中でも、肌の測色が比較的に多く用いられている。
肌の測色には一般的に、ＪＩＳＺ- ８７２２に規定される色の測定方法に準拠した色差計や分光光度計が用いられる。しかし、この測色法では、汎用されている測色器の測定可能面積がφ数ｍｍ〜φ２０数ｍｍ程度に限られていること、また、測定値の再現性の点からも測定部位は平坦であることが望まれるため頬や額などの部位にしか適していないことなど、顔全体からの測定には制限が多く、くすみという総合的な視覚現象を客観化するには困難がある。
【０００４】
顔全体を測色する場合、ＣＣＤカメラ等の電子的カメラによるＲＧＢ画像値を人の色彩感覚と一致したＬ^*ａ^*ｂ^*表色系等の色空間に変換している（１９９６- ２、ＦＲＡＧＲＡＮＣＥＪＯＵＲＮＡＬ、ｐ４７〜５４等）。その際、光源及び撮影装置に偏光板を組み込み測色部位の内部反射光成分に絞った測色を行っている場合もある（特許１９６００７５号等）。
皮膚の色は白い真皮の上にある表皮のメラニンと表皮直下血管網のヘモグロビンの量で殆ど決定される。正常皮膚に含まれる程度の量ではメラニンを含んだ層（主に表皮基底層）と血液層での入射光の散乱は少なく、吸収・透過のみが生じると言っても良い。一方、真皮は逆に入射光を殆ど乱反射し、光は再び血液層とメラニン層で吸収された後、人の眼において「肌色」とみえる。このことからも、内部反射光成分に主眼をおいた従来の皮膚の測色方法は、ほぼ、人の眼が感知している像を客観化していると考えられていた。
【０００５】
一方、皮膚の表面反射光成分に関しては、皮膚の構造からも干渉等を顕著に起こすとは考えにくいこと、入射光の表面反射光成分および表皮（主に角層）からの乱反射光成分の人の眼への影響は小さいこと、表面反射光成分は単純に光源色しか反映していないと考えられていることから、表面反射光成分からの皮膚の測色は殆ど為されていなかった。
しかし、人の眼が皮膚をみる場合、内部反射光成分以外も感知し、表面反射光成分を含めた総合的な認識を行っていることは確かである。だが、その表面反射光成分における「色」に関する知見は何ら得られていないのが現状である。
【０００６】
【発明が解決しようとする課題】
本発明はこのような状況を踏まえて為されたものであり、皮膚の表面反射成分からの測色方法及び評価方法を確立し、該評価方法を用いるスクリーニング法により選択された無機粉体組成物やそれを含有する化粧料を提供することにある。
【０００７】
【課題を解決するための手段】
このような状況を鑑みて、本発明者らは、人の皮膚の表面反射光成分を光学的に解明すべく鋭意研究を重ねた結果、皮膚のくすみの大きな要素の一つとして、表面反射光成分における色相、及び皮膚の表面反射光成分を得るための光源入射角とそれに対する受光角の組み合わせに光学的要素が存在することを見出した。光源の対象物に対する表面反射光成分の色特性は内部からの干渉光が存在しない限り光源色自身に由来する。人の皮膚は干渉を起こし難いためその成分の色特性は光源色に由来する。しかし、角質層を含む表皮層は半透明性を有するため、その狭角が75度以上の入受光角の組み合わせでは、レイリー散乱による色特性の付加が確認でき、この要素が肌のくすみを解消することに大きく寄与していることを見いだした。
【０００８】
散乱とは光が小さな粒子に当たって、方向が不規則に散らされる現象である。その散乱の強弱は光の波長と粒子の大きさに関係する。粒子の大きさが光の波長よりも大きい場合には、散乱の程度はどの波長でも一様で、例えば霧や雲の水滴によって散乱された光はどの波長も一様に散乱されるので白くみえる。ところが、粒子の大きさが光の波長以下になると、散乱の程度は各波長によって異なり、短波長（紫- 青）の光は長波長（橙- 赤）よりも散乱されやすく、この散乱をレイリー散乱と言う。青空の青みは大気中の微粒子により散乱された短波長の青い光を見ている。この大気中での現象が皮膚内モデルとして援用できる。例えば、太田母斑は表皮メラニン顆粒の不規則な増加が真皮にもおよび皮膚のレイリー散乱により短波長の青色が呈され、表皮のメラニン顆粒による褐色も混色され、褐青色にみえる。
【０００９】
本発明者らは、皮膚の法線方向に対して入受光の挟角が小さいと、光源の可視光全域波長の表面反射は僅かだけ生じ、残りは表皮を透過し真皮まで達するため、レイリー散乱を表皮中で生じることなく基底層のメラニンと真皮のヘモグロビンの吸収を受け、最終的に長波長が短波長よりも強い内部反射光成分として散乱されるが、皮膚の法線方向に対して入受光の挟角が７５度以上であると、表面反射光成分の増加によりレイリー散乱が強調され、特に、老いたくすみのある肌においては、表面反射光成分の強度とともにその程度が角質層の肥厚によって一層強くなることを見いだした。
【００１０】
このことは、老いた肌の明度が下がること、黄みが増大すること、美しい肌には青みの多さが重要であることなどがすべて光学的に説明できる。これらすべては皮膚の内部反射光成分についての現象である。皮膚表面反射光成分の視点からみると、その成分の増大により角層の厚い老いた肌では皮膚内部に入る光が減少し、明度が低下する。また、表皮反射光成分である青- 緑味が増大するため皮膚内部には青- 緑味の入光が減少するため内部散乱からの青- 緑味が減少し美しく見えない。さらに青- 緑味の減少により補色である黄みの散乱が相対的に増加し、また、表皮反射光成分及び表面反射光成分の人の視覚への影は軽微であることから、青- 緑味は内部反射光成分に覆われ、皮膚が黄み帯びてみえる。
【００１１】
本発明は、上記の知見に基づいて完成されたものであり、以下の各発明を包含する。
［１］皮膚の色を、
（１）偏光板が装着された電子的カメラの撮影装置を用いて皮膚の内部反射光成分を含む表面反射光成分を最も強調した画像及び皮膚の表面反射光成分を最も除去した画像をそれぞれ撮影する工程、
（２）前記両撮影画像の差分処理により皮膚の表面反射光成分画像を得る工程、ならびに
（３）前記表面反射光成分画像をＬ^＊ａ^＊ｂ^＊表色系に変換し、増幅する工程、を含んで成る方法で測定し、皮膚のくすみ解消に有効な無機粉体組成物を選択するにあたり、
（４）皮膚くすみを評価すべく被験者の皮膚評価部位における被験組成物塗布時の表面反射光成分のＬ^＊ａ^＊ｂ^＊表色系色度ａ^＊と色度ｂ^＊を（Ａａ^＊）と（Ａｂ^＊）、無塗布時の皮膚評価部位における表面反射光成分のＬ^＊ａ^＊ｂ^＊表色系色度ａ^＊と色度ｂ^＊を（Ｂａ^＊）と（Ｂｂ^＊）とした場合、（Ａａ^＊）＜０、（Ａｂ^＊）＜０、（Ｂａ^＊）＜０、（Ｂｂ^＊）＜０において、前記照射光の入射角が前記皮膚表面に対して２０〜７０度の何れかの角度である場合の受光角が前記皮膚表面に対して反射方向２０〜７０度の何れかの角度で、常に（Ａａ^＊）−（Ｂａ^＊）＞０、又は常に（Ａｂ^＊）−（Ｂｂ^＊）＞０、又は常に（Ｂａ^＊）×（Ｂｂ^＊）−（Ａａ^＊）×（Ａｂ^＊）＞０である無機粉体組成物を選択することを特徴とする皮膚のくすみ解消に有効な無機粉体組成物のスクリーニング方法。
【００１２】
［２］上記［１］記載のスクリーニング方法で選択された皮膚のくすみ解消に有効な無機粉体組成物であって、タルクに、酸化チタン、酸化アルミニウム、球状シリカおよびシリカをこの順に被覆し、その重量比がタルク：酸化チタン：酸化アルミニウム：球状シリカ：シリカ＝４０〜６０：３〜１３：８〜２０：８〜２４：５〜１５重量％であることを特徴とする皮膚のくすみ解消に有効な無機粉体組成物。
【００１３】
［３］上記［２］項記載の皮膚のくすみ解消に有効な無機粉体組成物を０．１〜９０重量％含有することを特徴とする化粧料。
［４］化粧料であることを特徴とする上記［２］項記載の皮膚のくすみ解消に有効な無機粉体組成物。
本発明に用いるタルクとしては、平均粒子径が２〜２０μｍで厚みが０．０５〜１μｍであることが好ましい。無機酸化物の被覆方法は、前記無機酸化物などの前駆物質の金属塩を加水分解する方法や、同様の金属アルコキシドをアルコール溶液中で加水分解する方法など、従来から無機酸化物の被覆方法として知られている方法であれば特に制限はない。例えば鱗片状基材を水中に分散させた物に四塩化チタンなどの金属塩を添加し、アルカリ雰囲気で加水分解し、鱗片状基材表面に金属塩加水分解物を析出させ所定の厚みの酸化チタン被覆層を得る方法などが挙げられる。また、シリカを被覆する場合には、鱗片状基材の分散液にアルカリ金属ケイ酸塩水溶液を添加し、鱗片状基材表面にケイ酸の重合物を付着させることにより、所定の厚みのシリカ被覆層を得る方法が挙げられる。
【００１４】
以上のように、基材に対する金属酸化物の被覆を順次おこない目的とする前記無機粉体組成物を得る。
【００１５】
【発明の実施の形態】
以下に本発明の実施形態を説明する。
本発明の皮膚のくすみ解消に有効な無機粉体組成物は、皮膚のくすみを評価すべく被験者の皮膚評価部位における被験組成物塗布時のＬ^*ａ^*ｂ^*表色系で表した表面反射光成分の色度ａ^*と色度ｂ^*を（Ａａ^*）と（Ａｂ^*）、無塗布時の皮膚評価部位における表面反射光成分の色度ａ^*と色度ｂ^*を（Ｂａ^*）と（Ｂｂ^*）とした場合、（Ａａ^*）＜０、（Ａｂ^*）＜０、（Ｂａ^*）＜０、（Ｂｂ^*）＜０において、前記照射光の入射角が前記皮膚表面に対して２０〜７０度の何れかの角度である場合の受光角が前記皮膚表面に対して反射方向２０〜７０度の何れかの角度で、常に（Ａａ^*）−（Ｂａ^*）＞０、又は常に（Ａｂ^*）−（Ｂｂ^*）＞０、又は常に（Ｂａ^*）×（Ｂｂ^*）−（Ａａ^*）×（Ａｂ^*）＞０であることを指標にスクリーニングされたものであり、化粧料として好適である。
【００１６】
本発明における皮膚表面反射光成分の色相の評価方法につきその一例を示す。
１）用いる照明光源下における標準白色を設定する。本発明では、３２００ケルビン（以下Ｋと記す。）の光源（株式会社ＬＰＬ製ブロムランプＪＣＤ１００Ｖ- ３００Ｗ）の拡散光をＪＩＳＫ５４００に沿った隠蔽力測定紙（太佑機械株式会社製）に１０度の方向から照射し、０度の受光角で６０ｃｍ離れ観察される白色を、白色点が６５００Ｋ、ガンマ値が０．４５、色空間がｓＲＧＢをもつデジタルカメラＣ- ２５００Ｌ（ＯＬＹＭＰＵＳ社製）にて変換標準化し標準白色として設定する。
【００１７】
２）皮膚表面に、前記光源からの拡散光を一方向から照射し、偏光板（株式会社ケンコー製Ｃ- ＰＬ（Ｗ））の装着された撮影装置にて前記皮膚表面を複数の受光角度で撮影する。ここで撮影する皮膚表面の部位は特に限定されないが、顔全体又は人の頬の撮影が適切な評価結果が得られることから好ましい。受光角度は、前記皮膚表面に対して前記照射光の入射方向と反対方向に０〜８０度、より好ましくは２０〜７０度である。その際、偏光板の回転により皮膚の内部反射光成分を含む表面反射光成分を最も強調した画像、並びに皮膚の表面反射光成分を最も除去した画像をそれぞれ撮影し、ファイルとして得る。
【００１８】
３）前記２）の方向とは異なる角度で前記拡散光を照射し、同様に皮膚の内部反射光成分を含む表面反射光成分を最も強調した画像、並びに皮膚の表面反射光成分を最も除去した画像をそれぞれ上記１）と同様に受光角度を変化させ複数撮影する。これらの撮影は、複数回、各々異なる角度の拡散光照射で行う。このとき、１）と２）の照射する光の皮膚表面に対する入射角は、０〜８０度、より好ましくは２０〜７０度である。
【００１９】
４）前記２）の前記皮膚の内部反射光成分を含む表面反射光成分を最も強調した画像ファイル並びに皮膚の表面反射光成分を最も除去した画像ファイルを、白色点が６５００Ｋ、ガンマ値が２．２２、色空間がｓＲＧＢに設定されたモニタにて、イメージ編集ソフト（アドビシステムズ株式会社製ＡｄｏｂｅＰｈｏｔｏｓｈｏｐ５．０）がインストールされたパーソナルコンピュータ（アップルコンピュータ株式会社製ＰｏｗｅｒＭａｃｉｎｔｏｓｈＧ３、ＭａｃＯＳ８．５）にて読み込み、両画像ファイルの差分処理により表面反射光成分画像を得る。同様に前記２）の前記皮膚の内部反射光成分を含む表面反射光成分を最も強調した画像並びに皮膚の表面反射光成分を最も除去した画像についても同様に行い表面反射光成分画像を得る。
【００２０】
５）前記表面反射光成分画像をＬ^*ａ^*ｂ^*表色系に変換し、ａ^*及びｂ^*色度を増幅した。その色度が皮膚の色相の指標となる。このとき増幅の倍率は１〜６、より好ましくは２〜５、さらに好ましくは２．５〜４．５である。前記３）の差分処理、並びに４）の表色系変換及び増幅処理には各処理が可能ならば特に限定されない。ここで、皮膚の表面反射光成分の色相を検出する方法として前記１）〜４）の手順を行ったが、表面反射光成分の色相の検出が可能であるなら特に限定されない。
【００２１】
６）かくして得られた様々な組み合わせをもつ皮膚の表面反射光成分における色相の傾向から皮膚のくすみを評価する。特に、照明光の皮膚表面に対する入射角が２０〜７０度で、受光角度が入射方向と反対方向の２０〜７０度で測定した表面反射光成分の色相についてくすみの評価を行うのがより好ましい。
図１及び図２は、Ｌ^*ａ^*ｂ^*表色系画像の中、輝度であるＬ^*画像を削除し、色相である色度ａ^*及び色度ｂ^*を重ね合わせた画像の例である。光源の入射角は顔面正面に対して０、２２．５、４５、６７．５度のそれぞれで照射し、撮影装置の受光角は前記顔面表面に対して反射方向に正の角度を表すとし、２２．５、４５、６７．５度とし、前記１）〜４）の手順により測定した場合における顔の表面反射光成分の色相である。図１は殆どくすみの観られない２１歳女性の顔全体についてのくすみの傾向を示し、図２はくすみの多く観られる５０歳女性の顔全体についてのくすみの傾向を示す。横軸は照射光の顔面表面に対する入射角で６７．５、４５、２２．５、０度と順に示し、縦軸は撮影装置の受光角で顔面表面に対する反射方向を正とし、６７．５、４５、２２．５、０度と順に示す。表色系変換後の色度増幅は３倍である。
【００２２】
図１と図２を比較した場合、６７．５度入射６７．５度受光、４５度入射６７．５度受光、２２．５度入射６７．５度受光、４５度入射４５度受光各々にて、加齢に伴い色度ａ^*及び／又は色度ｂ^*が減少していることが観察される。このことから、加齢に伴い特異的なこれら入射角受光角の組み合わせにおいて顕著な表面反射光成分の色相が見受けられ、この色相を抑制しくすみの殆どみられない皮膚と同等に近づければ、くすみの解消された仕上がりになることが判る。したがって、得られた表面反射光成分の色相の傾向を比較すれば無機粉体組成物や化粧料のくすみ解消程度を評価することができる。
【００２３】
本発明の無機粉体組成物は、好ましくは、タルクに、酸化チタン、酸化アルミニウム、球状シリカおよびシリカをこの順に被覆し、その重量比がタルク：酸化チタン：酸化アルミニウム：球状シリカ：シリカ＝４０〜６０：３〜１３：８〜２０：８〜２４：５〜１５重量％である。また、化粧料へ好適に配合するため、粉体表面の疎水処理を行うことが好ましい。
本発明の化粧料は特に限定されないが、ファンデーション又はおしろいが好適である。ルース型、固形、固形パウダー型、固形油性型、固形油中水型乳化型、油中水型乳化型、水中油型乳化型、二層分散油中水型、水性型等のいずれであってよく、ルース型、固形、固形パウダー型、固形油性型が好ましく、特に、ルース型おしろい、固形パウダー型及び固形油性型のファンデーションの場合に本発明の効果は最も発揮される。
【００２４】
前記化粧料に含まれる、前記無機粉体組成物の含有量は０．１〜９０重量％であるが、おしろいのルース型の場合はより好ましくは５〜３５重量％、固形の場合はより好ましくは７〜３０重量％であり、ファンデーションの固形パウダー型の場合はより好ましくは７〜３０重量％、固形油性型の場合は好ましくは０．１〜５０重量％、より好ましくは５〜２５重量％、固形油中水型乳化型、油中水型乳化型及び水中油型乳化型の場合は好ましくは０．１〜４０重量％、より好ましくは５〜２０重量％、二層分散油中水型の場合は好ましくは０．１〜３０重量％、より好ましくは５〜１５重量％、水性型の場合は０．１〜２０重量％、より好ましくは５〜１０重量％である。
【００２５】
本発明の化粧料は、上記必須成分に加えて本発明の効果を損なわない範囲で、通常化粧料、医薬部外品等に用いられる成分を配合することができる。このような成分としては、例えば水、油分、保湿剤、活性剤、前記以外の粉体、分散剤、防腐剤、香料、増粘剤等が挙げられる。
油分としては、例えば、エステル油、シリコーンオイル、鉱物油、炭化水素、ワックス、脂肪酸、脂肪族アルコール天然脂肪、油性ゲル化剤等が挙げられ、配合量としては、０．０１〜７０重量％が好ましい。
【００２６】
保湿剤としては、例えば、多価アルコール、ムコ多糖類等の水溶液、コラーゲンなどのタンパク質水溶液、糖類、アミノ酸水溶液等が挙げられ、配合量としては、０．００１〜３０重量％が好ましい。
粉体としては、例えば、無機顔料、有機顔料、シリコーン及びその誘導体、金属石鹸、フッ素化合物及びその誘導体、レシチン及びその誘導体、アミノ酸及びその塩等で表面処理された顔料等が挙げられ、配合量としては、０．１〜９９重量％が好ましい。
【００２７】
活性剤としては、例えば、脂肪酸エステル等の非イオン界面活性剤、レシチン及びホスフェートのような両性及び陰イオン界面活性剤、ポリエーテル変性シリコーンのようなシリコーン系活性剤等が挙げられ、配合量としては、０．０１〜２０重量％が好ましい。
【００２８】
【実施例】
次に、実施例をあげて本発明をより詳細に説明する。なお、本発明はこれら実施例にのみ限定されるものではない。
実施例１、比較例１および２の各粉体について、皮膚の表面反射光成分の色相に対する影響を前記の方法により評価した。
実施例１
タルク１００ｇを純水１L に添加して充分に分散し、これに二酸化チタンとして濃度２０％の硫酸チタニル水溶液７５ｇを加え攪拌しながら加熱し５時間沸騰させた。これを室温まで冷却し、濾過水洗し、１１０℃で乾燥させて、二酸化チタンの水和物が被覆されたタルクを得た。これを更に１００ｇ計量し７５０ｍL の純水中に添加しよく分散させたものを、酸化アルミニウムとして濃度１０％の塩化アルミニウム水溶液２６０ｇ及び尿素１６０ｇを水５００ｍL に溶かした溶液に加えてよく混合し９０℃で５時間加熱し、室温まで冷却した。これを濾過水洗し、１１０℃で乾燥後、更に６００℃で６時間加熱し、ニ酸化チタン、酸化アルミニウムで順次被覆されたタルクを得た。次に平均粒子径１２０μm 真球状シリカの濃度２０％モノエチレングリコールを分散媒とするシリカオルガノゾル７８ｇとイソプロパノール２００ｇの混合液を調製した。これに二酸化チタン、酸化アルミニウムで順次被覆されたタルク１００ｇを加え、室温で攪拌混合した。次いでこの分散液に５００ｇのエタノールを加え、更にアンモニア水を加えてｐH ９．５以上とし、液温を４５℃に加温した後、この温度とｐH を維持しつつ攪拌しながらシリカとして濃度２８．８％の正ケイ酸エチルと２８％アンモニア水を同時に２時間かけて添加した。正ケイ酸エチルの添加量は４５ｇであった。添加終了後、更に２時間攪拌した後、濾過洗浄し、１１０℃で乾燥して、ニ酸化チタン、酸化アルミニウム、球状シリカおよびシリカで順次被覆されたタルクを得た。また、その重量％はタルク：酸化チタン：酸化アルミニウム：球状シリカ：シリカ＝５４：８：１６：１２：１０である。
【００２９】
皮膚への粉体の塗布量は１５ｍｇ／ｃｍ²とした。その結果を表１に示す。
比較例１
実施例１で使用したタルクのみを、実際に皮膚に塗布した。皮膚への粉体の塗布量は１５ｍｇ／ｃｍ²とした。その結果を表１に示す。
比較例２
平均粒子径３００ｎｍの酸化チタンを、実際に皮膚に塗布した。皮膚への粉体の塗布量は１５ｍｇ／ｃｍ²とした。その結果を表１に示す。
【００３０】
被験者の皮膚評価部位における被験組成物塗布時のＬ^*ａ^*ｂ^*表色系で表した表面反射光成分の色度ａ^*と色度ｂ^*を（Ａａ^*）と（Ａｂ^*）、無塗布時の皮膚評価部位における表面反射光成分の色度ａ^*と色度ｂ^*を（Ｂａ^*）と（Ｂｂ^*）とした場合、（Ａａ^*）＜０、（Ａｂ^*）＜０、（Ｂａ^*）＜０、（Ｂｂ^*）＜０において、前記照射光の入射角が前記皮膚表面に対して２０〜７０度の何れかの角度である場合の受光角が前記皮膚表面に対して反射方向２０〜７０度の何れかの角度で、常に（Ａａ^*）−（Ｂａ^*）＞０、又は常に（Ａｂ^*）−（Ｂｂ^*）＞０、又は常に（Ｂａ^*）×（Ｂｂ^*）−（Ａａ^*）×（Ａｂ^*）＞０である場合を○、そうでない場合を×と評価した。
【００３１】
また、官能評価専門パネラー２１名を用いて、試料粉体を皮膚に塗布し、くすみ評価について官能評価を行った。評価基準はその項目が感じられる、やや感じられる、感じられないの３段階評価において、感じられる人数が１６〜２１名を○、６〜１５名を△、１〜５名を×とした。
【００３２】
【表１】

【００３３】
実施例１の無機粉体組成物は比較例１及び２よりも、くすみに有効で、老いた肌のくすみ解消に効果がある、優れた無機粉体組成物であった。
次に、表２に示す処方に従って化粧料を作成した。単位は重量％とした。
【００３４】
【表２】

【００３５】
ルース型おしろいについて、製法として、Ａ、Ｂをヘンシェルミキサーにて攪拌混合後、粉砕を行い、実施例２及び比較例３からなる化粧料を得た。
固形パウダー型ファンデーションについて、製法として、Ａを攪拌混合し粉砕を行い、混合溶解したＢを粉砕したＡとヘンシェルミキサーで攪拌混合し、再び粉砕を行い、金皿容器にプレスし、実施例３及び比較例４からなる化粧料を得た。
【００３６】
固形油性型ファンデーションについて、製法として、Ａ、Ｂを加熱溶解分散後、３本ロールミルを行い、７０℃で金皿容器に流し込み、実施例４及び比較例５からなる化粧料を得た。
図３は、実施例２及び比較例３のファンデーションを塗布した場合の皮膚表面反射光成分を示す。表面反射光成分評価における皮膚へのファンデーションの塗布量は１０ｍｇ／ｃｍ²とし、照射光の入射角は３５度、受光角は反射方向に６０度である。また、表３に光学的評価結果及び官能評価を含む総合評価を示す。実施例２のファンデーションは比較例３よりも、実施例３のファンデーションは比較例４よりも、実施例４のファンデーションは比較例５よりも、それぞれの剤型における化粧料にてくすみに有効で、老いた肌のくすみ解消に効果がある、優れた化粧料であった。
【００３７】
【表３】

【００３８】
【発明の効果】
本発明によれば皮膚のくすみを新たな客観的な方法で評価し、皮膚のくすみを解消する無機粉体組成物やそれを含む化粧料を提供することが可能である。
【図面の簡単な説明】
【図１】図１は、２１歳女性の、顔全体の表面反射光成分の色相を示す。
【図２】図２は、５０歳女性の、顔全体の表面反射光成分の色相を示す。
【図３】図３は、本発明の評価方法により有効性を示す表面反射光成分の色相画像データである。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to cosmetics containing the screening methods of effective inorganic powder compositions eliminate skin dullness, and inorganic powder compositions selected by the screening method and compositions thereof.
[0002]
[Prior art]
According to the Japan Cosmetic Industry Federation, 1995, 101, Japan Cosmetic Industry Association Technical Document, p148, “Dullness is a specific visual phenomenon. The whole face or around the eyes and cheeks. In the state where the redness of the skin decreases and the yellowness increases, and / or the brightness and transparency of the skin decreases, or the brightness appears to be reduced by shadows due to irregularities on the surface of the skin, Boundaries are unclear, ”defined as a diverse and comprehensive visual phenomenon.
[0003]
Items for measuring dullness using a measuring device include 1) lightness or hue of skin color, 2) nonuniformity of skin color, 3) unevenness of skin, 4) light transmittance, and 5) gloss value. Among them, skin colorimetry is used relatively frequently.
Generally, a color difference meter or a spectrophotometer conforming to the color measurement method defined in JIS Z-8722 is used for skin color measurement. However, in this color measurement method, the measurable area of a general-purpose colorimeter is limited to about several mm to several 20 mm, and the measurement site is flat from the viewpoint of the reproducibility of measured values. Therefore, it is difficult to make the overall visual phenomenon of dullness objective, because there are many restrictions on the measurement from the whole face, such as being suitable only for parts such as cheeks and foreheads.
[0004]
When measuring the color of the entire face, RGB image values obtained by an electronic camera such as a CCD camera are converted into a color space such as an L ^* a ^* b ^* color system that matches the human color sense (1996-2, FRAGRANCE JOURNAL, p47-54 etc.). At that time, there may be a case where a polarizing plate is incorporated in the light source and the photographing apparatus to perform colorimetry by focusing on the internally reflected light component of the colorimetric part (Japanese Patent No. 1960075 etc.).
Skin color is mostly determined by the amount of melanin in the epidermis over the white dermis and the amount of hemoglobin in the vascular network just below the epidermis. It can be said that the amount of light contained in normal skin causes little scattering of incident light in the melanin-containing layer (mainly the epidermal basal layer) and the blood layer, and only absorption and transmission occur. On the other hand, the dermis, on the other hand, almost diffusely reflects incident light, and the light is again absorbed by the blood layer and melanin layer, and then appears to be “skin color” in the human eye. For this reason as well, it has been considered that the conventional skin colorimetry method that focuses on the internally reflected light component objectively visualizes the image sensed by the human eye.
[0005]
On the other hand, with respect to the surface reflection light component of the skin, it is difficult to think that interference or the like is caused significantly from the skin structure, and the surface reflection light component of the incident light and the diffuse reflection light component from the epidermis (mainly stratum corneum) Since the effect on the eye is small and the surface reflected light component is considered to simply reflect only the light source color, skin color measurement from the surface reflected light component has hardly been performed.
However, when the human eye sees the skin, it is certain that it senses not only the internally reflected light component but also performs comprehensive recognition including the surface reflected light component. However, at present, no knowledge about the “color” in the surface reflected light component has been obtained.
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of such a situation, and establishes a colorimetry method and an evaluation method from a surface reflection component of the skin, and an inorganic powder composition selected by a screening method using the evaluation method Another object is to provide a cosmetic containing the same.
[0007]
[Means for Solving the Problems]
In view of such circumstances, the present inventors have conducted extensive research to optically elucidate the surface reflected light component of human skin, and as a result, surface reflected light is one of the major factors of skin dullness. It has been found that there are optical elements in the combination of the light source incident angle and the light receiving angle with respect to the hue in the component and the surface reflected light component of the skin. The color characteristic of the surface reflected light component with respect to the object of the light source is derived from the light source color itself unless there is interference light from the inside. Since human skin is less likely to cause interference, the color characteristics of its components are derived from the light source color. However, because the epidermal layer including the stratum corneum is translucent, it is possible to confirm the addition of color characteristics due to Rayleigh scattering when the narrow angle is 75 ° or more, and this element eliminates dull skin. I found that it contributed greatly to
[0008]
Scattering is a phenomenon in which light strikes a small particle and its direction is randomly scattered. The intensity of the scattering is related to the wavelength of light and the size of the particles. If the particle size is larger than the wavelength of the light, the degree of scattering is uniform at any wavelength, for example, light scattered by fog or cloud droplets appears to be white because all wavelengths are uniformly scattered . However, when the particle size is less than or equal to the wavelength of the light, the degree of scattering varies with each wavelength, and short wavelength (purple-blue) light is more likely to be scattered than long wavelengths (orange-red). Say scattering. The blueness of the blue sky sees short-wavelength blue light scattered by fine particles in the atmosphere. This atmospheric phenomenon can be used as an intradermal model. For example, Ota nevus has an irregular increase in the epidermal melanin granules in the dermis and a short wavelength blue due to Rayleigh scattering of the skin, and the brown color due to the melanin granules in the epidermis is also mixed and appears brown blue.
[0009]
The present inventors have found that when the incident light reception angle is small with respect to the normal direction of the skin, only a slight surface reflection of the visible light over the entire wavelength range of the light source occurs, and the rest passes through the epidermis and reaches the dermis. It is absorbed by the melanin of the basal layer and hemoglobin of the dermis without being generated in the epidermis, and finally the long wavelength is scattered as an internal reflection component that is stronger than the short wavelength, but it enters the normal direction of the skin. When the included angle of light reception is 75 degrees or more, Rayleigh scattering is emphasized due to an increase in the surface reflection light component, and in particular, in old and dull skin, the degree of the thickness of the stratum corneum increases with the intensity of the surface reflection light component. I found out that it would be even stronger.
[0010]
This can optically explain that the lightness of old skin decreases, yellowness increases, and that bluishness is important for beautiful skin. All of these are phenomena of the internally reflected light component of the skin. From the viewpoint of the reflected light component on the skin surface, the light entering the skin is reduced and lightness is lowered in the aged skin having a thick stratum corneum due to the increase in the component. In addition, since the blue-green taste that is the epidermis reflected light component is increased, the blue-green light incident is reduced inside the skin, so that the blue-green taste from the internal scattering is reduced and the skin does not look beautiful. In addition, the decrease in blue-green tint causes a relative increase in the scattering of the complementary yellow color, and the shadows on the human eye of the epidermis reflection component and the surface reflection component are negligible. The taste is covered with internally reflected light components and the skin appears yellowish.
[0011]
The present invention has been completed based on the above findings and includes the following inventions.
[1] The skin color
(1) Using an imaging device of an electronic camera equipped with a polarizing plate, an image in which the surface reflection light component including the internal reflection light component of the skin is most emphasized and an image in which the surface reflection light component of the skin is most removed are respectively taken. The process of
(2) a step of obtaining a surface reflection light component image of the skin by differential processing of the both photographed images; and (3) a step of converting the surface reflection light component image into an L ^* a ^* b ^* color system and amplifying it, In selecting an inorganic powder composition effective for eliminating dull skin,
(4) L ^* a ^* b ^* color system chromaticity a ^* and chromaticity b ^* of the surface reflected light component at the time of applying the test composition at the skin evaluation site of the subject to evaluate skin dullness and (Aa ^* ) (Ab ^* ), when L ^* a ^* b ^* colorimetric chromaticity a ^* and chromaticity b ^* of the surface reflected light component at the skin evaluation site without application are (Ba ^* ) and (Bb ^* ), In (Aa ^* ) <0, (Ab ^* ) <0, (Ba ^* ) <0, (Bb ^* ) <0, the incident angle of the irradiation light is any one of 20 to 70 degrees with respect to the skin surface. In the case of an angle, the light receiving angle is any angle in the reflection direction of 20 to 70 degrees with respect to the skin surface, and always (Aa ^* ) − (Ba ^* )> 0 or always (Ab ^* ) − (Bb ^* )> 0, or always ^{^{(Ba *) × (Bb *}} ) - (Aa *) × (Ab *)> 0 in which the inorganic powder composition selected The screening method of dullness effective inorganic powder composition to resolve the skin, characterized by.
[0012]
[2] are the above [1] valid inorganic powder composition dull eliminate skin selected by the screening method described, talc, coated titanium oxide, aluminum oxide, a spherical silica and silica in this order, the weight ratio of talc: titanium oxide: aluminum oxide: spherical silica: silica = 40-60: 3-13: 8-20: 8-24: dull skin characterized in that 5 to 15 wt% Inorganic powder composition effective for elimination.
[0013]
[3] A cosmetic comprising 0.1 to 90% by weight of an inorganic powder composition effective for relieving dullness of the skin described in [2 ] above.
[4] The inorganic powder composition effective for relieving dullness of the skin according to the above item [2], which is a cosmetic.
The talc used in the present invention preferably has an average particle diameter of 2 to 20 μm and a thickness of 0.05 to 1 μm. Inorganic oxide coating methods have been conventionally used as inorganic oxide coating methods, such as a method of hydrolyzing a metal salt of a precursor such as the inorganic oxide or a method of hydrolyzing a similar metal alkoxide in an alcohol solution. There is no particular limitation as long as it is a known method. For example, a metal salt such as titanium tetrachloride is added to a material in which a scaly substrate is dispersed in water, hydrolyzed in an alkaline atmosphere, and a metal salt hydrolyzate is deposited on the surface of the scaly substrate to oxidize to a predetermined thickness. Examples thereof include a method for obtaining a titanium coating layer. In addition, when coating silica, an alkali metal silicate aqueous solution is added to the dispersion of the scaly substrate, and a silica polymer is adhered to the surface of the scaly substrate, whereby silica having a predetermined thickness is obtained. The method of obtaining a coating layer is mentioned.
[0014]
As described above, the metal powder is sequentially coated on the base material to obtain the desired inorganic powder composition.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
The inorganic powder composition effective for relieving dullness of the skin of the present invention is a surface reflection expressed in the L ^* a ^* b ^* color system when the test composition is applied to the skin evaluation site of the subject in order to evaluate dullness of the skin. The chromaticity a ^* and chromaticity b ^* of the light component are (Aa ^* ) and (Ab ^* ), and the chromaticity a ^* and chromaticity b ^* of the surface reflected light component at the non-application skin evaluation site are (Ba ^* ). And (Bb ^* ), when (Aa ^* ) <0, (Ab ^* ) <0, (Ba ^* ) <0, (Bb ^* ) <0, the incident angle of the irradiated light is relative to the skin surface. (Aa ^* ) − (Ba ^* )> 0, and the light receiving angle in the case of any angle of 20 to 70 degrees is any angle in the reflection direction of 20 to 70 degrees with respect to the skin surface. always ^{^{(Ab *) - (Bb *}} )> 0, or always ^{^{(Ba *) × (Bb *}} ) - (Aa *) × disk to index the (Ab ^*)> 0 Are those that are Ningu, it is suitable as a cosmetic.
[0016]
An example of the method for evaluating the hue of the reflected light component on the skin surface in the present invention will be described.
1) Set a standard white color under the illumination light source to be used. In the present invention, the diffused light of a 3200 Kelvin (hereinafter referred to as K) light source (Blomp lamp JCD100V-300W manufactured by LPL Co., Ltd.) is applied to a concealing power measuring paper (manufactured by Dazai Kikai Co., Ltd.) according to JIS K 5400 at 10 degrees. A white camera with a white point of 6500K, a gamma value of 0.45, and a color space of sRGB is observed with a digital camera C-2500L (manufactured by OLYMPUS). Conversion is standardized and set as standard white.
[0017]
2) Diffuse light from the light source is irradiated on the skin surface from one direction, and the skin surface is exposed at a plurality of light receiving angles with a photographing apparatus equipped with a polarizing plate (C-PL (W) manufactured by Kenko Corporation). Take a picture. The part of the skin surface to be imaged here is not particularly limited, but imaging of the entire face or a person's cheek is preferable because an appropriate evaluation result can be obtained. The light receiving angle is 0 to 80 degrees in the direction opposite to the incident direction of the irradiation light with respect to the skin surface, more preferably 20 to 70 degrees. At that time, an image in which the surface reflection light component including the internal reflection light component of the skin is most emphasized by rotation of the polarizing plate and an image in which the surface reflection light component of the skin is most removed are photographed to obtain a file.
[0018]
3) The diffused light is irradiated at an angle different from the direction of 2), and the image in which the surface reflected light component including the internal reflected light component of the skin is emphasized most and the surface reflected light component of the skin is most removed. A plurality of images are taken by changing the light receiving angle in the same manner as 1) above. These photographing operations are performed a plurality of times by diffusing light irradiation at different angles. At this time, the incident angle with respect to the skin surface of the light irradiated by 1) and 2) is 0 to 80 degrees, more preferably 20 to 70 degrees.
[0019]
4) In the image file in which the surface reflection light component including the internal reflection light component of the skin in 2) is emphasized most and the image file in which the surface reflection light component of the skin is most removed, the white point is 6500K and the gamma value is 2. 22. Personal computer (Power Macintosh G3, MacOS 8.5 manufactured by Apple Computer Co., Ltd.) with image editing software (Adobe Photoshop 5.0 manufactured by Adobe Systems Co., Ltd.) installed on a monitor whose color space is set to sRGB The surface reflected light component image is obtained by the difference processing of both image files. Similarly, the surface reflected light component image is obtained in the same manner for the image in which the surface reflected light component including the internal reflected light component of the skin in 2) is most emphasized and the image in which the surface reflected light component of the skin is most removed.
[0020]
5) The surface reflected light component image was converted into the L ^* a ^* b ^* color system and a ^* and b ^* chromaticity were amplified. The chromaticity is an index of skin hue. At this time, the magnification of amplification is 1 to 6, more preferably 2 to 5, and further preferably 2.5 to 4.5. The difference processing of 3) and the color system conversion and amplification processing of 4) are not particularly limited as long as each processing is possible. Here, the procedures 1) to 4) were performed as a method for detecting the hue of the surface reflected light component of the skin, but the method is not particularly limited as long as the hue of the surface reflected light component can be detected.
[0021]
6) The dullness of the skin is evaluated from the tendency of the hue in the surface reflected light component of the skin having various combinations thus obtained. In particular, it is more preferable to evaluate the dullness of the hue of the surface reflected light component measured when the incident angle of the illumination light with respect to the skin surface is 20 to 70 degrees and the light receiving angle is 20 to 70 degrees opposite to the incident direction.
FIGS. 1 and 2 are examples of images obtained by deleting the L ^* image as the luminance from the L ^* a ^* b ^* color system image and superimposing the chromaticity a ^* and the chromaticity b ^* as the hue. is there. The incident angle of the light source is irradiated at 0, 22.5, 45, and 67.5 degrees with respect to the front of the face, and the light receiving angle of the photographing device represents a positive angle in the reflection direction with respect to the face surface, It is the hue of the reflected light component on the face when measured by the procedures 1) to 4) at 22.5, 45 and 67.5 degrees. FIG. 1 shows a dull tendency for the whole face of a 21-year-old woman with little dullness, and FIG. 2 shows a dull tendency for the whole face of a 50-year-old woman with a lot of dullness. The horizontal axis indicates the incident angle of the irradiated light with respect to the face surface in the order of 67.5, 45, 22.5, and 0 degree, and the vertical axis indicates the light receiving angle of the photographing apparatus with the reflection direction with respect to the face surface being positive, 67.5, It is shown in order of 45, 22.5 and 0 degrees. The chromaticity amplification after the color system conversion is three times.
[0022]
When FIG. 1 is compared with FIG. 2, 67.5 degrees incident 67.5 degrees received light, 45 degrees incident 67.5 degrees received light, 22.5 degrees incident 67.5 degrees received light, 45 degrees incident 45 degrees received light respectively It is observed that the chromaticity a ^* and / or the chromaticity b ^* decreases with age. From this, a remarkable hue of the surface reflected light component is seen in the combination of the incident angle and the light receiving angle specific with aging, and if this hue is suppressed to the same level as that of the skin that hardly suppresses dullness, It turns out that the dullness is eliminated. Therefore, the degree of dullness elimination of the inorganic powder composition or the cosmetic can be evaluated by comparing the hue tendency of the obtained surface reflected light component.
[0023]
In the inorganic powder composition of the present invention, preferably, talc is coated with titanium oxide, aluminum oxide, spherical silica and silica in this order, and the weight ratio thereof is talc: titanium oxide: aluminum oxide: spherical silica: silica = 40. -60: 3 to 13: 8 to 20: 8 to 24: 5 to 15% by weight. Moreover, in order to mix | blend suitably with cosmetics, it is preferable to perform the hydrophobic process of the powder surface.
The cosmetic of the present invention is not particularly limited, but a foundation or funny is suitable. Loose type, solid, solid powder type, solid oil type, solid oil-in-water emulsion type, water-in-oil type emulsion type, oil-in-water type emulsion type, two-layer dispersed water-in-oil type, aqueous type, etc. The loose type, solid, solid powder type, and solid oil type are preferable, and the effects of the present invention are most exhibited particularly in the case of loose type, solid powder type, and solid oil type foundations.
[0024]
The content of the inorganic powder composition contained in the cosmetic is 0.1 to 90% by weight, more preferably 5 to 35% by weight in the case of an interesting loose type, and more preferably in the case of a solid. Is 7 to 30% by weight, more preferably 7 to 30% by weight in the case of the solid powder type of the foundation, preferably 0.1 to 50% by weight, and more preferably 5 to 25% by weight in the case of the solid oily type. In the case of a solid water-in-oil emulsion type, a water-in-oil emulsion type and an oil-in-water emulsion type, preferably 0.1 to 40% by weight, more preferably 5 to 20% by weight, a two-layer dispersed water-in-oil type Is preferably 0.1 to 30% by weight, more preferably 5 to 15% by weight, and in the case of an aqueous type, 0.1 to 20% by weight, and more preferably 5 to 10% by weight.
[0025]
In the cosmetic of the present invention, in addition to the above essential components, components that are usually used in cosmetics, quasi-drugs, and the like can be blended as long as the effects of the present invention are not impaired. Examples of such components include water, oil, humectants, activators, powders other than those described above, dispersants, preservatives, fragrances, thickeners, and the like.
Examples of the oil component include ester oil, silicone oil, mineral oil, hydrocarbon, wax, fatty acid, fatty alcohol natural fat, oily gelling agent, and the blending amount is 0.01 to 70% by weight. preferable.
[0026]
Examples of the humectant include aqueous solutions such as polyhydric alcohols and mucopolysaccharides, protein aqueous solutions such as collagen, saccharides, amino acid aqueous solutions, and the like, and the blending amount is preferably 0.001 to 30% by weight.
Examples of the powder include inorganic pigments, organic pigments, silicone and derivatives thereof, metal soaps, fluorine compounds and derivatives thereof, lecithin and derivatives thereof, pigments surface-treated with amino acids and salts thereof, and the like. Is preferably 0.1 to 99% by weight.
[0027]
Examples of the active agent include nonionic surfactants such as fatty acid esters, amphoteric and anionic surfactants such as lecithin and phosphate, and silicone-based active agents such as polyether-modified silicone. Is preferably 0.01 to 20% by weight.
[0028]
【Example】
Next, the present invention will be described in more detail with reference to examples. In addition, this invention is not limited only to these Examples.
About each powder of Example 1 and Comparative Examples 1 and 2, the influence of the surface reflected light component of the skin on the hue was evaluated by the method described above.
Example 1
100 g of talc was added to 1 L of pure water and dispersed sufficiently. To this was added 75 g of 20% strength titanyl sulfate aqueous solution as titanium dioxide, heated with stirring and boiled for 5 hours. This was cooled to room temperature, washed with filtered water, and dried at 110 ° C. to obtain talc coated with a hydrate of titanium dioxide. 100 g of this was weighed and added to 750 mL of pure water and dispersed well. The mixture was added to a solution prepared by dissolving 260 g of 10% aluminum chloride aqueous solution and 160 g of urea in 500 mL of water as aluminum oxide, and mixed well. For 5 hours and cooled to room temperature. This was washed with filtered water, dried at 110 ° C., and further heated at 600 ° C. for 6 hours to obtain talc coated sequentially with titanium dioxide and aluminum oxide. Next, a mixed solution of 78 g of silica organosol having a dispersion medium of 20% monoethylene glycol having a mean particle size of 120 μm and a spherical silica was prepared and 200 g of isopropanol was prepared. To this was added 100 g of talc coated with titanium dioxide and aluminum oxide, and the mixture was stirred and mixed at room temperature. Next, 500 g of ethanol was added to this dispersion, and ammonia water was further added to adjust the pH to 9.5 or more. After the liquid temperature was increased to 45 ° C., the concentration of 28 as silica was maintained while stirring while maintaining this temperature and pH. 8% ethyl silicate and 28% aqueous ammonia were added simultaneously over 2 hours. The amount of normal ethyl silicate added was 45 g. After completion of the addition, the mixture was further stirred for 2 hours, filtered, washed, and dried at 110 ° C. to obtain talc coated sequentially with titanium dioxide, aluminum oxide, spherical silica, and silica. Moreover, the weight% is talc: titanium oxide: aluminum oxide: spherical silica: silica = 54: 8: 16: 12: 10.
[0029]
The amount of powder applied to the skin was 15 mg / cm ² . The results are shown in Table 1.
Comparative Example 1
Only the talc used in Example 1 was actually applied to the skin. The amount of powder applied to the skin was 15 mg / cm ² . The results are shown in Table 1.
Comparative Example 2
Titanium oxide having an average particle size of 300 nm was actually applied to the skin. The amount of powder applied to the skin was 15 mg / cm ² . The results are shown in Table 1.
[0030]
The chromaticity a ^* and chromaticity b ^* of the surface reflected light component expressed in the L ^* a ^* b ^* color system when the test composition is applied to the skin evaluation site of the subject are (Aa ^* ) and (Ab ^* ), and nothing. When (Ba ^* ) and (Bb ^* ) are the chromaticity a ^* and chromaticity b ^* of the surface reflected light component at the skin evaluation site at the time of application, (Aa ^* ) <0, (Ab ^* ) <0, When Ba ^* ) <0 and (Bb ^* ) <0, the light receiving angle when the incident angle of the irradiation light is 20 to 70 degrees with respect to the skin surface is reflected on the skin surface. (Aa ^* ) − (Ba ^* )> 0, or always (Ab ^* ) − (Bb ^* )> 0, or always (Ba ^* ) × (Bb ^* ) at any angle in the direction of 20 to 70 degrees. A case where-(Aa ^* ) × (Ab ^* )> 0 was evaluated as ◯, and a case where it was not so was evaluated as ×.
[0031]
Further, using 21 panelists specializing in sensory evaluation, sample powder was applied to the skin, and sensory evaluation was performed for dullness evaluation. In the evaluation criteria, the item was felt, felt slightly, and felt unsatisfactory, and the number of people felt was 16 to 21 people, 6 to 15 people were △, and 1 to 5 people were x.
[0032]
[Table 1]

[0033]
The inorganic powder composition of Example 1 was an excellent inorganic powder composition that was more effective in dullness and more effective in eliminating dullness in aged skin than Comparative Examples 1 and 2.
Next, cosmetics were prepared according to the formulation shown in Table 2. The unit was weight%.
[0034]
[Table 2]

[0035]
As for the loose-type candy, A and B were stirred and mixed with a Henschel mixer and then pulverized to obtain a cosmetic comprising Example 2 and Comparative Example 3.
For the solid powder type foundation, A was stirred and mixed and pulverized, and the mixed and dissolved B was stirred and mixed with the pulverized A and Henschel mixer, pulverized again, pressed into a metal dish container, Example 3 and A cosmetic comprising Comparative Example 4 was obtained.
[0036]
For the solid oil type foundation, as a manufacturing method, A and B were heated and dissolved and dispersed, followed by three-roll milling and pouring into a metal dish container at 70 ° C. to obtain a cosmetic comprising Example 4 and Comparative Example 5.
FIG. 3 shows skin surface reflected light components when the foundations of Example 2 and Comparative Example 3 are applied. The amount of foundation applied to the skin in the surface reflected light component evaluation is 10 mg / cm ² , the incident angle of the irradiated light is 35 degrees, and the light receiving angle is 60 degrees in the reflection direction. Table 3 shows comprehensive evaluation including optical evaluation results and sensory evaluation. The foundation of Example 2 is more effective for dullness in the cosmetics in each dosage form than Comparative Example 3, the foundation of Example 3 is more than Comparative Example 4, and the foundation of Example 4 is more than Comparative Example 5. It was an excellent cosmetic that was effective in eliminating dullness on old skin.
[0037]
[Table 3]

[0038]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, it is possible to evaluate the dullness of skin by a new objective method, and to provide the inorganic powder composition which eliminates dullness of skin, and the cosmetics containing the same.
[Brief description of the drawings]
FIG. 1 shows the hue of a surface reflected light component of the entire face of a 21-year-old woman.
FIG. 2 shows the hue of the surface reflected light component of the entire face of a 50-year-old woman.
FIG. 3 is hue image data of a surface reflected light component showing the effectiveness by the evaluation method of the present invention.

Claims

Skin color,
(1) Using an imaging device of an electronic camera equipped with a polarizing plate, an image in which the surface reflection light component including the internal reflection light component of the skin is most emphasized and an image in which the surface reflection light component of the skin is most removed are respectively taken. The process of
(2) a step of obtaining a surface reflection light component image of the skin by differential processing of the both photographed images; and (3) a step of converting the surface reflection light component image into an L ^* a ^* b ^* color system and amplifying it, In selecting an inorganic powder composition effective for eliminating dull skin,
(4) L ^* a ^* b ^* color system chromaticity a ^* and chromaticity b ^* of the surface reflected light component at the time of applying the test composition at the skin evaluation site of the subject to evaluate skin dullness and (Aa ^* ) (Ab ^* ), when L ^* a ^* b ^* colorimetric chromaticity a ^* and chromaticity b ^* of the surface reflected light component at the skin evaluation site without application are (Ba ^* ) and (Bb ^* ), In (Aa ^* ) <0, (Ab ^* ) <0, (Ba ^* ) <0, (Bb ^* ) <0, the incident angle of the irradiation light is any one of 20 to 70 degrees with respect to the skin surface. In the case of an angle, the light receiving angle is any angle in the reflection direction of 20 to 70 degrees with respect to the skin surface, and always (Aa ^* ) − (Ba ^* )> 0 or always (Ab ^* ) − (Bb ^* )> 0, or always ^{^{(Ba *) × (Bb *}} ) - (Aa *) × (Ab *)> 0 in which the inorganic powder composition selected The screening method of dullness effective inorganic powder composition to resolve the skin, characterized by.

A claim 1 effective inorganic powder compositions eliminate dull skin selected by the screening method described, talc, titanium oxide, aluminum oxide, a spherical silica and silica coated in this order, the weight ratio thereof talc titanium oxide: aluminum oxide: spherical silica: silica = 40-60: 3-13: 8-20: 8-24: effective for skin dullness eliminate you wherein from 5 to 15 wt% Inorganic powder composition.

A cosmetic comprising 0.1 to 90% by weight of an inorganic powder composition effective for eliminating dull skin according to claim 2 .

The inorganic powder composition effective for relieving dullness of the skin according to claim 2, which is a cosmetic.