| 摘要: | 由於 人們 生活環境的汙染物劇增 生活環境的汙染物劇增 生活環境的汙染物劇增 生活環境的汙染物劇增 ，導致臭氧層 導致臭氧層 受到破壞 ，大量的 紫外線穿越大氣層進入地表，造成許多的肌膚問題。因此，不只在白天 在白天 需要 做 好防曬的工作 好防曬的工作 ，還必須加強肌膚的防護措施。現今多重功效的保養品逐漸成為市場的趨勢，造成市售防護保養產品琳瑯滿目，但產品良莠參差不齊。含化學性防曬劑之產品，經陽光照射後防曬能力大打折扣。為了改善前述的問題，本研究擬採用多重乳化劑型 O/W/O 來開發品質及安定性較佳之防曬美白產品。
眾所熟知的O/W/O多重乳化產品亦稱為"乳液中的乳液"，他們在藥物和化妝品領域有很好的應用潛力，除了能保護活性物質，也能調整活性物質之釋放時間，但是此劑型具有嚴重的凝集、絮凝及乳化熱力學之不穩定傾向，本研究主要目的是開發一穩定的多重乳化劑型的美白防曬霜。首先以三種不同的界面活性劑進行研究。根據研究結果，最後選擇以GMS/EmulsifierII 作為 O/W/O 乳化劑型的乳化系統，其添加的功能性成分有防曬劑octyl methoxy cinnamate (PMCX) 與 avobenzone (P1789)及美白劑Ascorbyl palmitate (AP)。經過實驗步驟，調製得到多重乳化的美白防曬霜後，進行加速老化前後之測定與評估，物性評估為安定性（C％）、流變儀、粒徑分析儀；有效性評估為SPF測定儀及美白有效性。所有的美白防曬霜於加速老化前後皆呈現穩定且具切變減稀之流變行為。而黏度與粒徑大小會隨功能性成分加入的濃度不同而改變，當多重乳液加入防曬劑或美白劑時，黏度會增加。此外，AP加入後，SPF值在加速老化期間皆能維持穩定，但儲存安定性降低。在光老化方面，O/W/O劑型能使PMCX光分解的現象降低。而在美白能力方面，經研究結果顯示，乳液中所含基質對於in vitro的方法是具有很大的影響。所以in vitro的測定方法僅能用測定美白成分的抑制能力，美白乳霜產品的美白效果還是應以in vivo的方法來測定。
綜合研究結果，我們得到最佳的美白防曬霜（配方16），它具有高的SPF（32），45°加速老化可以穩定14天且具有良好的光安定性與符合美學的外觀。其組成成分如下: GMS 1.6%、Amphisol K 0.64%、Mineral oil 27.0%、PMCX 5.0%、P1789 2.0%、Emulsifier Ⅱ5.0% 、 GermabenII 0.64%、 Carbopol 1342 0.104% 、 Ascorbyl Palmitate 0.6% 、TEA 0.10%、D.W 57.316%。
In the past two decades, the increased amounts of UV radiation reach the surface of the earth due to the collapsed ozone layer. When we are overexposed to the circumstances of the UV sunlight, it may cause a number of skin troublesome such as spots, wrinkle, hyperpigmentation , and even skin cancer . Obviously, it is important for us to intensively protect the skin from the damage of the UV sunlight. Among the stage of protecting from the damage, wearing efficacy suncreams is popular and promising method. Although a variety of commercial suncreams are available, most of them always have a low stability in storage and SPF valve during the accelerated tests.
The o/w/o multiple emulsions are known as “emulsions of emulsions”. In theory they have significant potential in pharmacy and cosmetics providing prolonged release of active substances and protection of fragile substances. However, significant problems may arise due to their thermodynamical instability and strong tendency for coalescence, flocculation and creaming. This study is to develop a stable o/w/o multiple emulsions both containing UV filters and a whitening agent. There are three different types of emulsifiers were examined. GMS/EmulsifierII was selected as surfactants for optimizing the character of o/w/o emulsions. Regarding to the functional ingredients, octyl methoxy cinnamate (PMCX) and/or avobenzone (P1789) as UV filters, and ascorbyl palmitate (AP) as a whitening agent, were incorporated into the o/w/o emulsions to obtain o/w/o whitening suncreams. Their physicochemical properties and effectiveness on sun protection and depigmentation were characterized and their stability over the time was evaluated by rheological measurements, microscopic analysis, SPF measurements and whitening ability with or without the accelerated tests. All the obtained whitening suncreams exhibited a reasonable stability and shear- thinning rheological behavior before and after the ageing time. Concentration of the functional ingredients markedly affected the viscosity and the droplet size. The apparent viscosity of the multiple emulsions was increased by UV filters and/or AP whitening agent. In addition, AP was able to stabilize SPF during the accelerated tests but make the suncreams’ storage stability reduced. In photoageing tests, it showed that the use of o/w/o type allow octyl methoxy cinnamate having lower photodegradation. Regarding to the whitening ability, the results showed that many different matrix in multiple emulsion would influence the in vitro measurements and result in unaccepted and unexpected data. Therefore, it was considered that in vivo method should be selected for whitening emulsion samples.
Based on these findings, a desired whitening suncreams was obtained. With high SPF of (32), a stability at 45℃ testing for 14days, good photostability, and esthetic appearance, it is composed of GMS 1.6%、Amphisol K 0.64%、Mineral oil 27.0%、PMCX 5.0%、P1789 2.0%、 EmulsifierⅡ 5.0% 、 Germaben II 0.64%、 Carbopol 1342 0.104% 、 Ascorbyl Palmitate 0.6% 、TEA 0.10%、D.W 57.316%。 |
