Exhaust gas purification filter

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Exhaust gas purification filter with a porous catalytic layer applied thereon, e.g. from a slurry with an organic pore-forming material e.g. of length/diameter ratio of less than 1.5. The layer is applied to a substrate 1 comprising a plurality of porous partitions 5 forming cells 4, e.g. in honeycomb configuration, wherein the partitions form an exhaust gas flow path, and the catalytic layer having a thickness of 10 μm or greater (e.g. 10-50 microns) over at least 20% of the total length, the catalytic layer having a thickness of 10 μm or greater being absent on the partitions 15 mm from an outflow side 3, e.g. where a sealing plug may be inserted. The catalyst may contain platinum, palladium, an alkali metal, and a rare-earth metal. The void ratio of the catalytic feature is preferably below 50% and the partitions between 40-60% with mean pore diameter of 10-20 microns. The outflow side may have a catalytic layer of 10-40 microns 15 mm from the outflow side. The slurry may comprise foaming agents including surfactants. The filter is designed to reduce drying time and pressure loss.