certification

Ceramics

Applicable Products: Cerasil Pucca Mould

Slurry Thinners

When used in cement slurries, the sodium silicate solution deflocculates the clay minerals and lime components of the slurry. This is achieved through a combination of effect,. including: adsorption on the slurry particle surfaces; donation of sodium ions (Na+); and precipitation of calcaum ions (Ca++) in the slurry. The net effect of this deflocculation process is a reduction of the amount of water needed to maintain the slurry within a pumpable viscosity range.

Sodium silicate is preferred as the deflocculant in the preparation of stable suspensions of clay (clay slips) for pouring into porous plaster molds. In the clay slips the silica acts as a buffer for any alkali present. Because less water is needed, the clay slip is dense and the finished piece is therefore stronger. Less firing time in the mold is required, and there is little shrinkage as the pieces dry.

In processing raw clays, the deflocculating action of silicate separates impurities such as quartz, feldspar, mica, iron oxide, etc.