Method of making multilayer sheets for firestops or mounting mats

Abstract

A method of forming a multilayer sheet suitable for use as a mat for mounting a pollution control element or as a firestop. The method comprises providing one aqueous slurry and another aqueous slurry, each slurry containing inorganic materials suitable for making a mounting mat for a pollution control element or a firestop. The two aqueous slurries can be separated from one aqueous slurry. The method can also comprise depositing the one slurry onto a permeable substrate; partially removing water from the one slurry to form the one layer on the substrate; and depositing the other slurry onto the one layer. One layer is dried out of the one slurry and another layer is dried out of the other slurry so as to form the multilayer sheet.

Dependencies are inferred from the claim text.