Evaluation of pigment distribution in contact lenses with iris patterns by multiprobe analysis methods

Abstract Iris-patterned lenses have recently become popular in the field of soft contact (SCLs), and SCLs are typical examples an industrial application gel materials. As these patterns can be printed using oxidized-metal-containing pigments, oxidized metals may exposed on lens surface depending printing method, potentially accounting for various health hazards. To evaluate state metal surface, we analyzed colored layer, mainly consisting via multiple probing methods, such as transmission electron microscopy (TEM), scanning TEM with energy-dispersive X-ray spectroscopy, hard photoelectron absorption fine structure (XAFS). Furthermore, confirmed that XAFS conversion yield (CEY) fluorescence (FY) methods demonstrated high sensitivity toward revealing existence pigments. Thus, use a combination CEY FY facilitate effective distribution analysis elements interior materials cosmetic CLs.