Retarder for gypsum plaster and a process for retarding the setting of gypsum plaster by the use thereof

摘要

A retarder for gypsum plaster is provided which consists essentially of beta -hydroxy- beta -carboxy-isocaproic acid or a water soluble salt thereof. It has powerful retarding effect toward gypsum plaster and gives a solid product having much better mechanical strength than that encountered when an alkali metal salt of citric acid or powdered glue which are the ordinary set retarders are used. A process for retarding the setting of gypsum plaster by the use thereof, is also provided.