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題 名 | 防曬劑中超微細固態氧化物添加劑其光化學反應機制對防曬功能利弊之探討=The Photochemical Catalytic Mechamism and the Versatile Functions of the Superfine Solid Metal Oxide Additives in Sunscreen Cosmetics |
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作 者 | 彭瓊琿; 石瑩; 彭耀寰; | 書刊名 | 弘光學報 |
卷 期 | 31 1998.04[民87.04] |
頁 次 | 頁127-137 |
分類號 | 418.33 |
關鍵詞 | 防曬劑; 氧化鋅; 二氧化鈦; 光催化反應; Sun-screen agents; ZnO; TiO[feaf]; Photocatalysis; |
語 文 | 中文(Chinese) |
中文摘要 | 超微細氧化鋅及二氧化鈦為無機固體防曬劑,常用於防曬製劑配方中。二氧化鈦為極有效之UVB blacker,而氧化鋅則為極佳之UVA blacker。當適當之光源照射時可以藉由光催化反應引發電洞(hole)及電子(electron)之產生,前者與H O形成具強氧化力之OH;後者則消耗空氣進入水中之氧而形成超氧化態離子O ,並與H 產生一連串之反應而形成HO 以及H O ,均具強氧化力。於以上過程中氧化鋅及二氧化鈦經由反射吸收甚至強氧化力而具防曬效果。本實驗中,色素Acid Violet 42及有機防曬劑Eusolex 232(Phenylbenzimidazole sulfonic acid)(Octylmethoxycinnamate),以氧化鋅2.5g/L作光分解之結果顯示,若無空氣中之氧介入則不引起降解反應,而在通氧氣及紫外燈(365nm)之光照下,兩者均可在一小時內分解90%以上,以上之結果證明有機物質,或任何生物活性物質不可與氧化鋅及二氧化鈦相共參配,長時間之日照,可能引發皮膚與以上強氧化力物質(OH,O ,HO 以及H O 等)之長時間接觸,故即使有防曬劑塗敷,仍應避免長時間之日光浴。 |
英文摘要 | Super fine ZnO and TiO are inorganic sun-screen agents, the former is ineffective UVA blocker, while the latter is an excellent UVB blocker. In photocatalyzed reaction by ZnO or TiO , a "hole" and an electron are simultaneously produced. The "hole" reacts with H O to generate a strong oxidative species which in turn reacts with the dissolved oxygen, resulting in the formation of superoxide free radical anion O , on subsequent reaction with H to produce. HO and H O ZnO and TiO can act as effective sun-screen agents, through mechanism of reflectance, absorption, and probably by oxidizing effect. In present study, the dye Acid Violet 42 and an organic sun-screen agents Eusolex 232(Phenylbenzimidazole sulfuric acid) in presence of dissolved oxygen and 2.5g/LZnO were shown degraded to 90% within 1 hour exposure to UV light (365nm). Results indicate the incomparability of ZnO or TiO2 with any possible organic ingredients. A long term exposure to UV may causeskin damages by those strong oxidizing species(OH, O , HO , and H O ) besides bleaching. The warning "A long period exposure of skin to sunlight should be avoided even though sun-screen tan has been applied", seems worth being recommended. |
本系統中英文摘要資訊取自各篇刊載內容。