Rheological studies of mineral clay and its application in reactive dye printing of cotton
We studied the rheological properties of mineral clay (OMC) and sodium alginate (SA) pastes using steady shear, dynamic oscillatory, and transient tests. The results showed that OMC was a viscoplastic fluid and had more obvious shear-thinning features than SA, which fitted well to the Herschel–Bulkley model. Under strain, OMC and SA exhibited elastic and viscous behavior, respectively, within the linear viscoelastic region. The viscosity of OMC returned to >60% of the initial viscosity after the removal of the high shear stress. In printing experiments, the color yield and penetration of OMC surpassed that of SA and offered excellent outline sharpness, suggesting that it has the potential to be used as a thickener for reactive dyes in cotton printing.