Precipitated silica containing active agent

摘要

Precipitated silica that contains an active agent and provides delayed release of the active agent is new. Also claimed is a process for preparing a product as above, in which precipitated silica is produced in known manner and a moderately to sparingly water-soluble active agent is added to the precipitation medium or the precipitate suspension or is dried together with the washed and optionally redispersed silica paste or is ground together with the dried material.