大石昌嗣先生、保坂啓一先生らの論文「Effects of mixing of europium oxide in resin composites on the fluorescence characteristics and mechanical properties」が掲載されました。

 

掲載誌等：BDJ Open, 11, 1, 9, 2025.
DOI：10.1038/s41405-025-00304-0
著者：Yuta Utsumi, Masatsugu Oishi, Kazuhide Yonekura, Masaomi Ikeda, Yusuke Matsuki, Kenichiro Ohge, Tomoki Iuchi and Keiichi Hosaka

 

要約：The objective of this study is to disperse europium oxide (EuO in a resin composite (RC) using a planetary centrifugal mixer and assess its effects on photoluminescence and mechanical properties. A commercially available RC was mixed with EuO at various concentrations using a planetary centrifugal mixer. The fabricated samples were evaluated using scanning electron microscopy and a spectrofluorometer to assess their crystal structures, particle sizes, and photoluminescence properties. Vickers microhardness measurements were performed, along with a three-point bending test. Statistical analyses were performed to assess the mechanical properties. The intensity of red fluorescence increased with the increase of europium oxide concentration. The fluorescence spectra at 613 and 620 nm exhibited higher intensities under excitation at 254 nm. EuO was dispersed in RC regardless of the EuO concentration, and no aggregation was observed. Regarding the mechanical properties, there were no significant differences in the flexural strength or modulus, and the Vickers hardness gradually increased with increasing EuO concentration. To mix EuO with RC, visible fluorescence emission was observed even with increasing the EuO concentration, and the mechanical properties of RC were unaffected. Based on our study, a 15 wt% concentration of Eu2O3 is the appropriate concentration, as it achieves strong fluorescence emission without compromising the mechanical properties or color tone of the RC.