CoO-ZnO-Cr₂O₃-TiO₂-SnO₂系スピネル固溶体の生成とその色

抄録

This study was concerned with the formation and color development of the spinel solid solution in CoO-ZnO-Cr₂O₃-TiO₂-SnO₂ system, and its application to colored glazes.
Specimens were prepared by calcining the oxide mixture at 1400°C for 1hr. The formation of spinel solid solution was examined by X-ray diffraction, the color was discussed by measuring the spectral reflectance, and the stability of the spinel in glazes was tested.
The results were summarized as follows.
1) Formation of a continuous solid solution was confirmed by X-ray analysis.
2) As the amount of Cr³⁺ increased in ZnO-Cr₂O₃-SnO₂ system, the color changed from white through grayish olive green to grayish leaf, and the absorption of Cr³⁺ shifted towards violet region.
3) An increase of Cr³⁺ in ZnO-Cr₂O₃-TiO₂ system caused the color to change from white through leaf to grayish leaf, and the absorption of Cr³⁺ shifted towards violet region.
4) The color obtained in ZnO-Cr₂O₃-TiO₂-SnO₂ system ranged from leaf to yellowish green.
5) An increase of Cr³⁺ in CoO-ZnO-Cr₂O₃-SnO₂ system yielded the colors ranging from grayish leaf through grayish olive green to strong blue green, and the absorption of Cr³⁺ shifted towards violet region.
6) As the amount of Cr³⁺ increased in CoO-ZnO-Cr₂O₃-TiO₂ system, the colors ranging from dark yellow through olive to strong blue green developed, and the absorptions of Co²⁺ and Cr³⁺ shifted towards violet region.
7) As the amount of Ti⁴⁺ increased in CoO-ZnO-TiO₂-SnO₂ system, the color changed from grayish leaf through grayish yellow to dark yellow, and the absorption of Co²⁺ shifted towards red region.
8) The colors ranging from leaf to olive developed in CoO-ZnO-Cr₂O₃-TiO₂-SnO₂ system.
9) According to the result of the colored glaze test, formation of a new spinel was observed, and the specimens with the composition of Cr³⁺ rich region were stable as a glaze stain.