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Ultraviolet light screen using cholesteric liquid crystal capsules on the basis of selective reflection.

ABSTRACT: Sunscreen can protect human skin from sunlight by decreasing exposure to ultraviolet (UV) light, specifically UV-B and UV-A. In this study, a new type of UV screen system is proposed using cholesteric liquid crystal (CLC) capable of selectively reflecting UV-A within the human skin temperature range of 32-36 °C. Polycaprolactone (PCL) capsules with CLC mixture which had a helical chiral pitch corresponding to the wavelength of UV light were made by a solvent evaporation method. The average diameter of the capsules was about 34 μm. Consequently, it was confirmed that the CLC mixture (COC : CN = 80 : 20) could reflect UV-A light over 350-380 nm within the human skin temperature range. Also, it was confirmed that the CLC/PCL microcapsules could block UV light over 290-400 nm by about 6%.

SUBMITTER: Oh H

PROVIDER: S-EPMC9037046 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Ultraviolet light screen using cholesteric liquid crystal capsules on the basis of selective reflection.

Oh Heemuk H Kikuchi Hirotugu H Lee Ji Hyun JH Kim Su Ji SJ Lee Jun Bae JB Cho Moon Sun MS Lee Min Young MY Okumura Yasushi Y Hong Joo-Hee JH Hong Sung-Kyu SK

RSC advances 20210722 41

Sunscreen can protect human skin from sunlight by decreasing exposure to ultraviolet (UV) light, specifically UV-B and UV-A. In this study, a new type of UV screen system is proposed using cholesteric liquid crystal (CLC) capable of selectively reflecting UV-A within the human skin temperature range of 32-36 °C. Polycaprolactone (PCL) capsules with CLC mixture which had a helical chiral pitch corresponding to the wavelength of UV light were made by a solvent evaporation method. The average diame ...[more]

PMID: 35478880

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