Study On The Property Of Wax And Ge Ware Crackle On The Wax Printing Fabric

In this thesis, the dewaxing technologies of the wax printing factories were investigated. It was found that the effects of currently used dewaxing methods were poor leading to serious pollution to the effluents and the COD was as high as 10 thousands ppm. At the same time the consumption in running equipment and installations were huge, for instance, the extent of wax recovery by air-flotation method could reach up to 80% during the first two weeks of production, then the extent of wax recovery dropped quickly to a level of 40-50% because the releaser was easy to be jammed and the Bio-Membrane was easy to grow on the fill in dissolved air tank leading to poor running efficiency. Thus, a novel dewaxing technique was invented and it could remove the wax directly from the fabric in hot water and recover the wax effectively. It was well known that the wax was softened and liquidized in hot water, with the interfacial tension making the liquidized wax scrunch into drops and thus the adhesion of wax to the fabric being decreased. The wax drops would separate from the fabric and then float upward to the water surface because of smaller density of wax drop. The hot water dewaxing method was completely based on the physical principles and no auxiliaries and chemicals were needed, so the recovered wax could be greatly preserved. The recovered wax could be reused directly for the wax printing and the extent of wax recovery reached up to 95%. This greatly reduced the cost and what more important was that it made great contribution to environment protection. The inventions about dewaxing technique, "The Equipment for Dewaxing from the Fabric" and "The Equipment & Method for Dewaxing from the Fabric", have been respectively authorized (Patent authorization No. CN2709451Y) and declared publicly (Patent application No. 200410062080).The properties of the printing waxes, e.g. the thermal properties, the rheological property of the molten waxes at different temperatures were also systematically investigated. The softening point of wax tested by Ring-and-Ball Apparatus method provided exact data of thermal property of wax and the analysis of softening point of waxes showed that the property of wax mixture was related closely to its ingredient but not changed strictly by the ratio of mixture. The study of the rheological property of wax by Haake 150 showed that the rosin(above 120℃), the paraffm(above 90℃), the bee-wax(above 90℃), the mixture of rosin and paraffin(above 90℃), the mixture of rosin and bee-wax(above 90℃) belong to the Newton type. The shear stress increased with increase in shear velocity and the viscosity didn't change with increase in shear velocity and it was just related to the kind and the working temperature of wax. The molten wax lost the fluidity as soon as it's printed on the fabric making wax pattern precise and clear. Based on the results of study, a new patterning method that could give a vivid and vigorous pattern, the so-called Ge ware crackle was invented (Patent application No. 200510110400.9). There were five famous wares in Song Dynasty, in the middle of which was the Ge Ware ceramic which was famous for its changeable and active crackles on the whole body. The principle that Ge Ware crackles formed was the result of the different thermal expansion coefficients (TEC) between the embryo and the glaze. When the TEC of the glaze was bigger than that of the embryo, the glaze layer would be in tensile stress state and experience the action of tensile stress. Once the tensile stress exceeded the limitation of elasticity and intensity, the glaze layer would tend to crackle. In case of the wax printed fabric, the different TEC between the fabric(embryo) and the wax layer(glaze) made the crackles happen. Furthermore, the fabric could be controllable in production and thus different Ge ware crackles could come into being. The result of experiment in this paper showed that clear and nature Ge Ware crackles came into being on fabric when some wax layers were moved into the cooling chamber with the temperature difference of over 35℃.