ALGINIC ACID SALT IMPRESSION MATERIAL COMPOSITION FOR DENTAL USE

PURPOSE:To provide the subject composition containing an alginic acid salt having low molecular weight and a hydroxyl compound, having high affinity to water and improved kneadability, and giving a formed gypsum having improved surface smoothness and gel strength. CONSTITUTION:The objective alginic acid salt impression material composition for dental use is produced by compounding 8-30wt.% (preferably 10-25wt.%) of an alginic acid salt having low molecular weight (e.g. having a viscosity of about 5-100cPs measured as 1% aqueous solution at 20 deg.C using a type-B rotary viscometer) and combining the salt with a hydroxyl compound (e.g. polyethylene glycol, glycerol or hydroxypropyl cellulose). The composition has improved kneading workability since an alginic acid salt having low molecular weight can easily be swollen or dissolved in water to give a solution having low viscosity. Furthermore, the properties such as strength can be improved because the alginic acid salt content can be increased compared with conventional composition. The coating with the hydroxyl compound is effective for increasing the swelling property and solubility of the impression material in water and improving the kneading workability.