METHODS FOR MANUFACTURING POROUS CERAMIC FILTERS AND COMPOSITIONS FOR APPLYING TO CERAMIC HONEYCOMB BODIES

摘要

Disclosed are compositions for applying to honeycomb bodies. The compositions can be used as plugging mixtures for forming a ceramic wall flow filter. Alternatively, the compositions can be used to form skin coatings on exterior portions of a honeycomb body. The disclosed compositions include an inorganic powder batch composition, an organic binder, a liquid vehicle, and a rheology modifier. The compositions exhibit improved rheological properties, including an increased yield strength and reduced viscosity under shear, which, among various embodiments, can enable the manufacture of sintered phase end plugs having reduced levels of dimple and pinhole formations in the final dried and fired end plugs as well as end plugs having relatively uniform and desired depths. Also disclosed are methods for forming end plugged ceramic wall flow filters from the plugging mixtures disclosed herein.