公开(公告)号：JPH11236325A

公开(公告)日：1999-08-31

申请号：JP34721498

申请日：1998-12-07

Applicant: DEGUSSA

Inventor： ESCH HEINZ ,  KUHLMANN ROBERT ,  NEUMUELLER MATTIAS ,  OTTO KARIN ,  RAUSCH RALF DR ,  THOMAS KLAUS-PETER

IPC: A61K8/21 ,  A61K8/25 ,  A61Q11/00 ,  A61K7/18

Abstract: PROBLEM TO BE SOLVED: To prepare the subject silicic acid capable of satisfying requirements for a medicine concerning compatibility, rheology characteristics, sensory irritation and the like, capable of fixing an active material in an oral cavity and allowing the active material to be controllably released, and useful as an oral hygienic good such as a toothpaste by allowing the active material to be carried. SOLUTION: This precipitated silicic acid containing an active material can carry out the sustained lease of the active material [e.g. a fluoride ion-containing material such as an alkali (alkaline earth) metal fluoride and fluoroapatite], and is prepared, for example, by previously inserting water and the active material in a precipitation vessel, heating the obtained mixture at 50-100 deg.C, adding (Z) a sodium silicate solution to the heated mixture while keeping the temperature to regulate the pH or the alkali metal content of the mixture, further adding the component Z and sulfuric acid while keeping the pH or the content of the alkali metal constant, further adding the sulfuric acid to acidify the obtained mixture so as to have pH 7, optionally carrying out an after-stirring of the resultant mixture, filtering and washing the resultant mixture, redispersing the obtained filtration cake, drying the redispersed filtration cake by a spray drier, and pulverizing the obtained dried silicic acid granule.