Atsunori Shiraishi
Saga Ceramics Research Laboratory
Novel green colors of the overglaze decorations were developed by using environment-friendly new green pigments and lead-free frits. The pigments were easy to be pulverized to fine powder and hard to be melted in the frit at the temperature of preparing the overglaze. The colors of the overglaze decoration fired at 800℃ on porcelain panels were brilliant green and were quite different from the conventional green colors using lead-free frits.
Atsunori Shiraishi
Saga Ceramics Research Laboratory
The purpose of this study is development of red color overglaze using cupper component. Several kinds of reductant agents were added to prepare overglaze using cupper. Finally, Pink color overglaze were derived by adding Si and Al powder as reductant agents. According to the result of XAFS analysis, the state of cupper in the pink overglaze was very similer to that in red glaze “Shinsha”. Therefore, it is considered that red color overglaze could be obtained as same as “Shinsha” using cupper.
Yuzo Shiwa
Saga Ceramics Research Laboratory
This study was aimed for the technical establishment that could measure the determination of trace impurities in high purity stabilized zirconia to lower limit level around 0.001wt% by ICP-AES. Microwave hydrothermal treatment apparatus was used for the pretreatment of the sample. Zirconia powder for matrix was dissolved in sulfuric acid(1+2) solution with a small amount hydrofluoric acid in a short time. Stabilized zirconia was dissolved only in sulfuric acid(1+2) in a short time. There was the element of the low sensitivity that could not support with a demand lower limit level with the ICP-AES apparatus which we used for determination in this study. But as for pretreatment method of this study and the method for measurement, a validity was confirmed by the result value of a measurement of the Ceramic Society of Japan certified reference material and the comparison of the certification value. And measurement accuracy of trace impurities was possible to around 0.001wt%.
Hiromichi Ichinose1,Masahiro Kugishima2,Kohjiro Hara3
1Saga Ceramics Research Laboratory
2Research Center for Photovoltaic Technologies, National Institute of Advanced Industrial Science and Technology
Potential-induced degradation (PID) of crystalline Si photovoltaic module was estimated by applying -1000V from cover glass to Si cell at 85℃. Concentration of Na-species on Si cell surface rather increased after PID test, and solar energy-to-electricity conversion efficiency decreased remarkably. When titanium dioxide thin films were coated onto the inside of the cover glass, prepared at 200℃ using peroxotitanium complex, anatase sol and a mixture of peroxotitanium complex and SiO2 sol, Na-species diffusion from cover glass to Si cell surface and PID were significantly prevented. Especially thicker film more than 100nm using prexotitanium complex was sufficient to completely suppress PID.
Masahiro Kugishima,Hiromichi Ichinose
Saga Ceramics Research Laboratory
We have reported on the preparation and properties of peroxotitanium complex which can be coated onto various materials because of their neutral pH and excellent adhesion to various substrates1). In this study, we explored the improvement of the dye-sensitized solar cell performances using TiO2 photoelectrodes modified with peroxotitanium complex. Porous TiO2 photoelectrodes were prepared on conductive oxide coated substrates by low-temperature (<150˚C) fabrication processes. The solar cell with optimized fabrication method yielded conversion efficiency of 4.4% for incident solar energy of 100mW/cm2.
Hiroaki Katsuki
Agriculture,Forestry,Fisheries & Commerce Head Office,Saga Pref.Gov.
In this research study, some properties of Yamase clay which was weathered from a granite stone for Karatsu ware(Ko-Karatsu) were investigated, and compared with those of Hobashira clay prepared from a weathered sand stone. Content of Al2O3 in Yamase clay was 30.8～33.1 mass%, and showed higher aluminous clay than Hobashira clay from a weathered sand stone(13.1～15.8 mass%). Yamase clay had fine tubular halloysite crystals with α-quartz, muscovite and feldspar. Bulk densities of Yamase clay fired at 1200, 1300, and 1400℃ for 1h were 1.99, 2.15, 2.35 g/cm3, respectively, and had a lower sintering behavior than Hobashira clay. After firing Yamase clay over 1300℃, the fired body was composed of fine needle-like mullite(48～53mass%) and glass(41～48mass%) without α-quartz, muscovite and feldspar. Furthermore, in this study, some properties of Ko-Karatsu ware shards produced at Yamase kiln and Hobashira kiln sites in the end of 16th century were discussed with data of Nanshitsu-jiki produced at the south area of the Korean peninsula from 15 to 17th century.