Sodium Silicate (Na₂SiO₃)
Sodium silicate, also known as "glass water", is a highly versatile chemical compound that performs multiple functions in ceramics. In its liquid form, it is mainly used as a deflocculant in slip and slips, improving the fluidity of mixtures by dispersing clay particles. This allows working with lower water content, which reduces shrinkage during drying and minimizes the risk of deformation.
In addition to its role in the preparation of slip, sodium silicate is also used in decorative techniques. For example, when applied to the surface of a raw piece, it can create unique crackle effects during drying. This effect is especially exploited in artistic ceramics, where crackle patterns add texture and visual depth to the pieces. In kiln construction, sodium silicate is used as an adhesive for bonding refractory bricks, thanks to its ability to withstand high temperatures. It is also used in the manufacture of molds and ceramic supports, where it acts as a hardener.Interesting Fact
Sodium silicate was originally developed for industrial applications, but its use has spread to ceramics because of its unique properties. It is also used in other fields, such as construction, cleaning and paper manufacturing.Helpful Tip
Use sodium silicate sparingly in slip, as excessive amounts can cause overdeflocculation problems and make it difficult for the material to cohere. If using it to create decorative effects, apply an even coat and experiment with different drying times to adjust the level of crackle. Always work in a well-ventilated area and wear gloves to protect your skin.
