Hoffmann Group introduced its products Silfit Z 91, Aktifit AM and Aktifit VM for applications in elastomers, paint and varnish, and thermoplastics. Silfit Z 91 is a naturally occurring conglomerate of amorphous and crypto-crystalline silica with lamellar kaolinite, which has been subjected to a heat treatment. The components and the thermal process lead to a calcined product that offers special performance benefits as a functional filler. Aktifit is an activated Silfit Z 91, produced by modifying the surface with functional silanes. The by-products split off during the treatment reaction are largely removed during the production process, which firmly attaches the silane to the filler surface. This helps minimize undesirable side effects, as they are potentially encountered with insitu mixing (direct addition of silane to the compound).