With the aim of developing Pb-free Bi₂O₃-based new solder glasses; glass forming region, glass transition temperature, crystallization temperature, thermal expansion, and water resistance of Bi₂O₃-BaO-B₂O₃ ternary glass system were investigated. The roles of Bi₂O₃ in this ternary glass were also discussed. The results showed that glass transition temperature and thermal expansion coefficients of the ternary glasses were in similar range as compared to those solder glass consisting PbO. The water resistance of ternary glass was almost the same as compared to window glass, but it is higher than solder glass containing PbO. The glass transition temperature of ternary glass was dependent on average bond strength. Our results also showed that as the amount of Bi₂O₃ increased, the average bond strength was decreased which lead to decrement of glass transition temperature. These results suggested that Bi₂O₃ plays an important role as glass network former in the glass system.

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In this study of the phosphor utilizing a scallop shell, it was researched that the luminescence center was estimated from the chemical composition of the shell for the final purpose of the improvement of the luminescence property. The luminescence centers were estimated to be Cu and Mn from the experiment result and literature investigation. Furthermore, these concentrations were small by more than two orders in comparison with the commercially available phosphors. Therefore, improvement of the luminescence property can be expected by doping Cu and Mn to the shell and to investigate the relationship between these concentrations and the luminescence property to find the optimum concentration.

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