Effects of Firing Atmosphere on the Color Manifestation of Celadon

Effects of firing atmosphere on the color manifestation of celadon were studied. The firing atmosphere was obtained by the combustion of LPG, which generates CO gas during incomplete combustion, which acted as the reducing agent. The amount of CO gas increased as the amount of injected LPG gas increased. As the amount of generated CO gas was few little, the a* and b* values was high, which exhibits a brown color. When the amount of CO gas increased, the a* and b* decreased, resulting in a deep blue color. The residual oxygen analysis result suggested that the amount of residual oxygen in the glaze decreased as the firing atmosphere changed towards reduction. This can be explained by the oxidation of the CO gas into CO2 by seizing a large amount of oxygen in the glaze.