【発明の詳細な説明】[Detailed description of the invention]
（技術分野）
本発明は、チオクト酸アミドを配合してなる皮
膚化粧料に関する。更に詳しくは、皮膚老化防止
効果（荒肌改善効果、角質改善効果、角質層のタ
ーンオーバーを速くする効果、美肌効果等）の優
れた化粧料に関する。
（従来技術）
老化皮膚とは、乾燥して滑らかさのない荒れ肌
で、角質細胞の剥離現象が認められ、結合組織は
コラーゲン／エラスチン比が高く、しわが多い。
また、老化皮膚は細胞代謝の低下により角質層の
ターンオーバーが遅く、従つて皮膚に老化防止効
果が付与発現するとターンオーバーが速くなると
言われ、種々の皮膚組織賦活成分が研究されてい
る。
しかし、皮膚の組織機能を修復または改善し、
皮膚が元来保有する機能を回復して皮膚の老化防
止効果に著効を示す程度に改良された皮膚化粧料
を得ることは困難であつた。
（発明の開示）
そこで、本発明者は、上記の事情に鑑み鋭意研
究した結果、チオクト酸アミドを配合してなる皮
膚化粧料は老化皮膚のターンオーバーを速め荒肌
改善効果、角質改善効果に著効を呈すると共に皮
膚に湿潤性（しつとり感）、柔軟性（滑らか感）、
弾力性（張り）及び艶を付与し得る美肌効果をも
発現することを見出して本発明を完成するに至つ
た。
（発明の目的）
即ち、本発明の目的は、皮膚老化防止効果（荒
肌改善効果、角質改善効果、角質層のターンオー
バーを速くする効果、美肌効果等）の優れた皮膚
化粧料を提供することである。
（発明の構成）
チオクト酸アミド
を0.05〜1.0重量％含有してなる皮膚化粧料であ
る。
本発明の皮膚化粧料中に配合せるチオクト酸ア
ミドは、皮膚組織を賦活し、皮膚が本来備えてい
る機能を修復或いは改善して皮膚を健常な状態に
保持し、特に老化皮膚に適用する場合、顕著な効
果が認められる。
チオクト酸アミドの配合量は、皮膚化粧料の総
量を基準として0.05〜1.0重量％（以下、wt％と
略記する）であり、0.05wt％未満では本発明の目
的とする効果が充分でなく、一方、1.0wt％を超
えてもその増加分に見合つた効果の向上は得られ
ない。
本発明の皮膚化粧料は、例えばローシヨン類、
乳液類、クリーム類、パツク類等に適用すること
ができる。
尚、本発明の皮膚化粧料には上記の他に色素、
香料、防腐剤、界面活性剤、顔料、抗酸化剤等を
本発明の目的を達成する範囲内で適宜配合するこ
とができる。
（実施例）
以下、実施例及び比較例に基づいて本発明を詳
説する。
尚、荒肌改善効果試験、角質改善効果試験、角
質層のターンオーバー測定試験、官能テスト（美
肌効果試験）は下記の通りである。
(1) 荒肌改善効果試験
下脚に荒れ肌を有する中高年被験者20名を対象
として４週間連続塗布効果を調べた。被験者の左
側下脚試験部位に１日１回約1gの試料を塗布し、
試験開始前および終了後の皮膚の状態を下記の判
定基準により判定した。右側下脚は試料を塗布せ
ず対照とした。
皮膚乾燥度の判定基準
− ：正常
± ：軽微乾燥、落屑無し
＋ ：乾燥、落屑軽度
＋＋ ：乾燥、落屑中等度
＋＋＋：乾燥、落屑顕著
試験前後の試験部位と対照部位の判定結果を比
較し、皮膚乾燥度が２段階以上改善された場合
（例えば＋→−、＋＋→±）を有効、１段階改善さ
れた場合をやや有効、変化がなかつた場合を無効
とした。試験結果は有効、やや有効となつた被験
者の人数で示した。
(2) 角質改善（角質細胞の抗剥離性増大）効果試
験
前述の荒肌改善効果試験開始前および終了後の
被験部皮膚にスコツチテープ（ニチバンメンデイ
ングテープ）を接着し、これを剥離した時テープ
に付着した角質細胞の状態を走査型電子顕微鏡に
よつて詳細に調べ、下記の基準によつて皮膚角質
細胞抗剥離性を解析し、角質改善効果を求めた。
角質改善効果（角質細胞抗剥離性増大）の判定基
準
評価点１ スケールを認めず
２ 小スケール点在
３ 小〜中スケール顕著
４ 大スケール顕著
評価は４週間連続塗布後の試験部位の評価点と
対照部位のそれとの差が２点以上の場合を有効、
１点の場合をやや有効、０点の場合を無効とし
た。判定結果は有効、やや有効となつた被験者の
人数で示した。
(3) 角質層のターンオーバー測定試験
螢光色素のダンシルクロライドを白色ワセリン
中に５重量％配合した軟膏を作り、被検者20名の
前腕部の皮膚に24時間閉塞貼付し、角質層にダン
シルクロライドを浸透結合させる。その後同じ部
位に１日２回（朝・夕）被検試料を塗布し、毎日
ダンシルクロライドの螢光をしらべ、その螢光が
消滅するまでの日数を皮膚角質層のターンオーバ
ーとした。
測定結果は各被検者の日数の平均値で示した。
なお、通常の皮膚角質層のターンオーバーは14〜
16日であるが、老化した皮膚においては18日前後
にのびる。それに対して老化防止効果が現れると
12日前後にまで短縮される。
(4) 官能テスト（美肌効果試験）
荒れ肌、小じわ、乾燥肌等を訴える女子被験者
（35〜55才）20人に試料を１日２回（朝夕）連続
３ケ月塗布して３ケ月後の効果を評果した。試験
結果は、皮膚の湿潤性、平滑性、弾力性の各項目
に対して、皮膚に潤いが生じた、皮膚が滑らかに
なつた、皮膚に張りが生じたと回答した人数で示
した。
実施例１〜３、比較例１
〔二層型スキンローシヨン〕
下記の組成のごとく二層型スキンローシヨン基
剤にチオクト酸アミドを第１表に記載の通りに配
合して各々のスキンローシヨンを調製し、前記諸
試験を実施した。
尚、チオクト酸アミドの基剤中の配合特性（溶
解性、分散性、保存安定性）は、調製時の配合特
性と各々恒温室（温度０℃、20℃、45℃）に３ケ
月間保存後の外観を肉眼観察して評価した。
(1) 組成
(Technical Field) The present invention relates to a skin cosmetic containing thioctic acid amide. More specifically, the present invention relates to cosmetics with excellent skin aging prevention effects (improving rough skin, improving keratin, accelerating the turnover of the stratum corneum, beautifying skin, etc.). (Prior Art) Aging skin is rough skin that is dry and lacks smoothness, exhibits peeling of corneocytes, has a high collagen/elastin ratio in connective tissue, and has many wrinkles.
Furthermore, in aging skin, the turnover of the stratum corneum is slow due to a decrease in cell metabolism, and therefore, it is said that the turnover becomes faster when an anti-aging effect is imparted to the skin, and various skin tissue activating ingredients are being studied. However, it can repair or improve skin tissue function,
It has been difficult to obtain skin cosmetics that have been improved to the extent that they restore the functions originally possessed by the skin and exhibit significant anti-aging effects on the skin. (Disclosure of the Invention) Therefore, as a result of intensive research in view of the above circumstances, the present inventor has found that a skin cosmetic containing thioctic acid amide accelerates the turnover of aging skin and has an effect on improving rough skin and improving keratin. It is highly effective and provides moisture (moist feeling), flexibility (smooth feeling) to the skin,
We have completed the present invention by discovering that it also has a beautifying effect by imparting elasticity (tightness) and luster to the skin. (Object of the Invention) That is, the object of the present invention is to provide a skin cosmetic with excellent skin aging prevention effects (improving rough skin, improving keratin, accelerating the turnover of the stratum corneum, beautifying skin, etc.). That's true. (Structure of the invention) Thioctic acid amide A skin cosmetic containing 0.05 to 1.0% by weight of The thioctic acid amide blended into the skin cosmetics of the present invention activates skin tissue, restores or improves the skin's inherent functions, and maintains the skin in a healthy state, especially when applied to aging skin. , a remarkable effect was observed. The blending amount of thioctic acid amide is 0.05 to 1.0% by weight (hereinafter abbreviated as wt%) based on the total amount of the skin cosmetic, and if it is less than 0.05wt%, the desired effect of the present invention will not be sufficient. On the other hand, even if it exceeds 1.0wt%, the effect cannot be improved commensurate with the increase. The skin cosmetics of the present invention include, for example, lotions,
It can be applied to milky lotions, creams, packs, etc. In addition to the above, the skin cosmetic of the present invention also contains pigments,
Flavors, preservatives, surfactants, pigments, antioxidants, and the like can be added as appropriate within the range that achieves the purpose of the present invention. (Examples) Hereinafter, the present invention will be explained in detail based on Examples and Comparative Examples. The rough skin improvement effect test, the stratum corneum improvement effect test, the stratum corneum turnover measurement test, and the sensory test (skin beautification effect test) are as follows. (1) Effect test on improving rough skin The effect of continuous application for 4 weeks was investigated on 20 middle-aged and elderly subjects who had rough skin on their lower legs. Approximately 1 g of the sample was applied to the test site of the subject's left lower leg once a day,
The condition of the skin before the start of the test and after the end of the test was evaluated according to the following criteria. No sample was applied to the right lower leg, which served as a control. Judgment criteria for skin dryness -: Normal±: Slight dryness, no flaking+: Mild dryness, flaking++: Moderate dryness, flaking+++: Dryness, significant flaking Compare the judgment results of the test site and control site before and after the test, The test was considered valid if the skin dryness improved by two or more levels (for example, +→-, ++→±), slightly effective if the skin dryness improved by one level, and invalid if there was no change. The test results are shown in terms of the number of subjects who were found to be effective or somewhat effective. (2) Effect test on improving keratin (increasing anti-peeling properties of keratinocytes) Scotch tape (Nichiban Mending Tape) was adhered to the skin of the test area before and after the start and end of the rough skin improvement effect test described above, and when it was peeled off, the tape The condition of the keratinocytes attached to the skin was examined in detail using a scanning electron microscope, and the anti-exfoliation property of skin keratinocytes was analyzed according to the following criteria to determine the keratin improving effect.
Judgment criteria for keratin improving effect (increased anti-desquamation property of keratinocytes) Evaluation points: 1 No scale observed 2 Small scale scattered 3 Small to medium scale noticeable 4 Large scale noticeable Valid if the difference from the control site is 2 or more points.
A score of 1 point was considered somewhat effective, and a score of 0 was considered invalid. The judgment results are expressed as the number of subjects who found the test to be effective or somewhat effective. (3) Test for measuring the turnover of the stratum corneum. An ointment containing 5% by weight of the fluorescent pigment dansyl chloride in white petrolatum was prepared and applied to the skin of the forearms of 20 subjects for 24 hours, and the ointment was applied to the skin of the forearms of 20 subjects. Osmotic binding of dansyl chloride. Thereafter, the test sample was applied to the same area twice a day (morning and evening), and the fluorescence of dansyl chloride was examined every day, and the number of days until the fluorescence disappeared was defined as the turnover of the stratum corneum of the skin. The measurement results were shown as the average value of the number of days for each subject.
In addition, the normal turnover of the skin's stratum corneum is 14~
It takes about 16 days, but in aging skin it can last around 18 days. On the other hand, when anti-aging effects appear
It will be shortened to around 12 days. (4) Sensory test (skin beautification effect test) The sample was applied twice a day (morning and evening) for 3 consecutive months to 20 female subjects (35-55 years old) who complained of rough skin, fine wrinkles, dry skin, etc., and the effect after 3 months. was evaluated. The test results were shown by the number of people who answered that their skin was moist, smooth, or taut for each item of skin wettability, smoothness, and elasticity. Examples 1 to 3, Comparative Example 1 [Two-layered skin lotion] Each skin lotion was prepared by blending thioctic acid amide into a two-layered skin lotion base as shown in Table 1, as shown in Table 1. A sample was prepared and the various tests described above were conducted. In addition, the formulation characteristics (solubility, dispersibility, storage stability) of thioctic acid amide in the base are the formulation characteristics at the time of preparation and those stored in a constant temperature room (temperature 0℃, 20℃, 45℃) for 3 months. The subsequent appearance was visually observed and evaluated. (1) Composition
【表】
(2) 調製法
(C)成分を(B)成分中に配合して(A)、(B)成分を各々
均一に溶解した後、(A)成分(B)成分を混合撹拌分散
し、次いで容器に充填する。使用時には内容物を
均一に振盪分散して使用する。
(3) 特性
各二層型スキンローシヨンの諸試験を実施した
結果を第１表右欄に記載した。
比較例１のチオクト酸アミドを配合していない
スキンローシヨンに比較して、本発明皮膚化粧料
は諸試験に於いて良好な結果が認められた。
尚、配合特性は、調製時及び恒温室中で保存テ
ストに於いて、異常は無かつた。
実施例４〜５、比較例２
〔スキンクリーム〕
実施例１と同様に、下記の組成にて各々のスキ
ンクリームを調製し、諸試験を実施した結果を第
１表右欄に示した。
(1) 組成[Table] (2) Preparation method After blending component (C) into component (B) and uniformly dissolving components (A) and (B), mix and disperse components (A) and (B). and then fill containers. When using, shake and disperse the contents uniformly. (3) Characteristics The results of various tests conducted on each two-layer skin lotion are listed in the right column of Table 1. Compared to the skin lotion of Comparative Example 1 which did not contain thioctic acid amide, the skin cosmetic of the present invention gave better results in various tests. There were no abnormalities in the blending characteristics during preparation and during storage tests in a constant temperature room. Examples 4 to 5, Comparative Example 2 [Skin Cream] In the same manner as in Example 1, skin creams were prepared with the following compositions and various tests were conducted.The results are shown in the right column of Table 1. (1) Composition
【表】【table】
【表】
(2) 調製法
(C)成分を(B)成分中に配合して、(A)成分及び(B)成
分を各々80℃に加熱溶解した後、混合して、撹拌
しつつ30℃迄冷却して各スキンクリームを調製し
た。
(3) 特性
第１表に示すごとく、本発明の皮膚化粧料であ
る実施例４〜５のスキンクリームは、比較例２と
比較して諸特性のすべてに亘つて優れていること
は明らかであり、配合特性に於いても異常は認め
られ無かつた。[Table] (2) Preparation method: Blend component (C) into component (B), heat and dissolve each component (A) and (B) at 80℃, mix, and stir for 30 minutes. Each skin cream was prepared by cooling to ℃. (3) Properties As shown in Table 1, it is clear that the skin creams of Examples 4 and 5, which are skin cosmetics of the present invention, are superior to Comparative Example 2 in all of the properties. No abnormalities were observed in the blending characteristics.
【表】
（発明の効果）
以上記載のごとく、本発明は、皮膚組織を賦活
して皮膚の老化防止に顕著な効果を発現する優れ
た皮膚化粧料を提供することが明らかである。[Table] (Effects of the Invention) As described above, it is clear that the present invention provides an excellent skin cosmetic that activates skin tissue and exhibits a remarkable effect on preventing skin aging.