Sodium Silicate Molding Sands

Molding sands with water glass belong to the group of sands which are human and environment-friendly. Water glass as a binder of molding sands has been known since the middle of the twentieth century. Irreversible reactions, occurring between water glass and liquid hardeners (organic esters) or CO2, are applied for molding sand hardening. In order to improve disadvantageous properties of these sands (e.g., bad knocking out), water glass is subjected to physical or chemical modifications. As a result of such modifications, the water glass-based new binders, environmental-friendly, are formed. The known world companies from many years are performing investigations of molding sands (CORDIS®, Huttenes Albertus; INOTEC®, ASK Chemicals; AWB®, Minelco), where water glass hardening occurs as a result of warming core boxes and core blowing by hot air.