脂肪醇/水/油形成液晶型乳化體之研究

Liquid Crystal Emulsion Formed by Fatty Alcohol/ Oil/Water

嚴珮慈(Pei-Tzu Yen)

指導教授 ： 芮祥鵬

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2013年)

摘要

乳液系統是經常應用於許多產業如食品、藥品、化妝品上，乳液可大致分為水包油型O/W (Oil in water) 及油包水型W/O (Water in oil) 兩大類，並且他們可調整配方來達到不同的應用。文獻指出水包油型乳化系統具有可形成液晶結構的特性，液晶乳液可以幫助皮膚吸收與乳液之穩定性，因為液晶結構是與我們人體皮膚的表皮層有相似結構，故塗抹在肌膚上具有良好的吸收性，並能在肌膚上形成保濕薄膜提升肌膚的滋潤，此次我們經由添加脂肪醇幫助促進液晶的形成，並調整不同的配方來研究液晶的形成機制，在不同的溫度下測試液晶的穩定性，最後我們測試液晶乳液的肌膚保濕性，來確認液晶乳液的保濕特性。
本論文研究分為兩部分，第一部份是以調整配方比例來建構 ”脂肪醇 / 水 /油” 之相圖，並探討三相圖在室溫時的狀態，為了探討液晶型態在溫度變化間的相變化，我們調整了不同的溫度來測試：低溫4℃、15℃，高溫：35℃、45℃。第二部份則探討此系統之基本性能，並將結果與相圖進行分析。我們將脂肪醇/水/油三相圖系統分為5個相區。5個相區分別是乳液(Emulsion)、液晶型乳液(Liquid Crystal Emulsion)、半固態乳液(Semisolid Emulsion)、固態乳液(Solid Emulsion)、油水分離相(Oil-Water Separation)。
在分析相圖後，我們發現添加越多脂肪醇會使乳液的流動性變差，外觀會從乳狀轉向半固態或固態，同時也更不容易形成液晶，因此僅在配方中具有適量的脂肪醇下，才能形成液晶型乳液，過量的脂肪醇並不會形成液晶。在控溫穩定性測試中，我們發現低溫不會影響液晶區，但是升溫至45℃時，乳液液晶區會微幅縮小，表示升溫時比較容易影響液晶的穩定性。保濕測試也顯示具有液晶型態的乳液有著極佳的保濕性，可確認液晶型乳液能讓皮膚更加保濕。

關鍵字

相圖 ； 液晶 ； O/W乳液

並列摘要

The emulsion system is widely used in many industry like food, pharmacy, and cosmetics. We can classify emulsion into two types: O/W (Oil in Water) type and W/O (Water in Oil) type. By modulating their formulation, we can get different application. It is said that O/W emulsion system has the property to form liquid crystal, and liquid crystal emulsion can enhance the percutaneous absorption and stability. Because liquid crystal emulsion has similar structure to our skin epidermis, it will have better penetration while apply on the skin. Furthermore, it can also form a hydration film on the skin to increase the moisture. In our research, we added fatty alcohol to enhance the formation of liquid crystal. By modulating the formulation, we had discovered the formation mechanism of liquid crystal emulsion. To investigate its liquid crystal stability, we tested in different temperature. At the end we had applied liquid crystal emulsion on the skin and test the moisture efficacy to ensure the hydration ability.
This research is divided into two parts. The first part we adjusted the percentage of formulations to create the phase diagram of Fatty Alcohol / Water / Oil, and we had discussed the 3-phase diagram status in room temperature. In order to investigate the liquid crystal phase transition in different temperature, we had modulated the temperature to low temperature (4℃ and 15℃) and high temperature (35℃ and 45℃). The second part of our research is to discuss the basic properties of this system. We had proceed the analysis between different phase diagram and result discussion. We had classified this system into 5 areas in our phase diagram of Fatty Alcohol / Water / Oil. The 5 areas is Emulsion, Liquid Crystal Emulsion, Semisolid Emulsion, Solid Emulsion, and Oil-Water Separation.
After analysis our phase diagram, we had found that by adding more content of fatty alcohol will influence emulsion’s fluidity. The emulsion appearance will change from creamy to semisolid or solid. Also, it is less likely to form the liquid crystal in emulsion. During the temperature controlling test, we had found that there is no change inside the liquid crystal area in low temperature. On the contrary, in high temperature we had discovered the liquid crystal area will become slightly smaller. As a result, while we increase the temperature, it will influence the stability of liquid crystal. Through moisturizing test, we had found that liquid crystal emulsion has excellent hydration effect to ensure it can moisture the skin.

並列關鍵字

Phase diagram ； the liquid crystal ； O / W emulsions

參考文獻

[1]U.S. Food and Drug Administration (2011, June 27).Cosmetics & U.S. Law.Retrieved July 2, 2004. from

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