The rheological behaviors of screen-printing pastes

Typically, the printing paste consists of vehicles and inorganic powders, in which vehicles refer to solvent, resin and additives and inorganic powders refer to functional powders and glass powders. A variety of functional pastes are prepared depending on printing needs, while rheological behaviors such as the paste liquidity, thixotropy, and viscoelastic properties will influence printing quality. This study is designed to measure the yield stress, thixotropy, and viscosity at different shear rates of commercially available screen-printing pastes and self-prepared pastes by using a rheometer. In addition, it dynamically measures rheological properties such as viscoelastic. This study also involves the discussion over the viscosity change of commercially available pastes at various shear rates to acquire the association between paste liquidity and printing. Also, with the preparation of vehicles and pastes, the study is intended to observe the impact of various fillers on paste rheological behaviors in a steady-state and dynamic rheological test, offering a reference for selection of solution during paste preparation and using the effects of binders and fillers on the systemʹs rheology to control the conditions, e.g. viscosity, thixotropy and viscoelasticity, for preparation of pastes that fit screen-printing requirements.