Study On Forming Mechanism And Production Technology Of Oil-drop Glaze

Oil-drop glaze is one of the valuable glazes, which was mainly produced in Jianan, Fujian province and Jizhou, Jiangxi province in Nansong dynasty. It is reported that this valuable historic inheritance will be lost. Because of its special decorating effect, many ceramics researchers have studied on it and the conclusion is not very unanimous. The idea of forming mechanism of oil-drop glaze is not very clear and the technological control of imitations varies to some extent. Special natural clay is used in most present oil-drop glaze products, which lead to some limitation. Today it is a blank to produce oil-drop glaze in Hebei province. It will extremely promote the development of art ceramics if we deeply probe into its forming mechanism and technological conditions and imitate it successfully, which will enrich our art ceramics decorating means and make it more actively in intense competition.After inheriting the formers researching result and learning from present oil-drop glaze producers, the writer dug into the forming mechanism of oil-drop glaze and described the forming process in detail by means of comparative experiment, dynamic observing, SEM (scan electronic microscope), and some other modern analysis methods. It is discovered that oil-drop forms in the period when temperature rises during firing process. Through dynamic observing, it is proved that under the proper firing rules the forming of oil-drop will experience a series stages from phase separation, nucleation, crystal growth, to liquating properly. The liquating of crystal is useful to its shape and size and a thin layer of glass will bring about which is helpful to glaze gloss. Through cross experiment design, the reasonable range of oil-drop glaze chemical composition is studied and the limitation that single special clay is added to glaze batch is broken. It is proved that using ordinary ceramic raw materials to produce oil-drop glaze is feasible if the chemical composition of glaze is reasonable and the technology control is suitable. In addition, through the experiment it is found out that proper firing rule is the critical factor that affects the oil-drop glaze decorating effect. At the same time, other technological factors, for example, the thickness of glaze layer, glazing method, the size of glaze particle, which can affect the quality of glaze surface, must be considered.The success of this research will be helpful to development of oil-drop glaze, which is the magnificent cultural inheritance, and will bring new decorating means to modern arts ceramics. We will have a beautiful prospect.