The relative absorbance is directly proportional to the stabilityof dispersion. The decrease of the relative absorbance indicates thedecrease in dispersion stability, in other words, an increase in disper-sion instability. The relative absorbance values at 850 nm of 2%w/vceramic glaze suspensions in the absence and presence of SDBS atconcentrations of 0.6, 2.0 and 3.5 mM in the three media as a func-tion of time are measured and shown in Figs. 6-8. Without SDBS,the dispersion stability increased slightly with increasing the MgCl2concentration. Less than 10% of the suspension remained after onehour. In the presence of SDBS, the stability of suspension increasedwith increasing the concentration of SDBS, especially in deionizedwater and 0.001 M MgCl2 media much higher relative absorbancewas investigated.In the presence of 2.0 mM and 3.5 mM of SDBS, the glaze sus-pension after one hour in deionized water and in 0.001 M MgCl2was more than 86% remaining, while that in 0.1 M MgCl2 mediumless than 12% of the suspension remained. This should be in agree-qeKf1n---CelogloglogFig. 4. Linear plots of Freundlich isotherm of SDBS on ceramicglaze in three media.Fig. 5. Diagram illustrating the adsorption of DBS on the surfaceof ceramic glaze in the presence of MgCl2.