A fluid feed ring (5), a substrate coating apparatus (1) and a method are provided for coating a substrate (2) with a catalyst component. The fluid feed ring (5) comprises an annular body (40) having an inner face (45) bounding a central bore of the fluid feed ring. A fluid feed port (47) receives the liquid and a plurality of outlet apertures (50) on the inner face of the annular body discharge the liquid onto a piston face (23) of the substrate coating apparatus (1). A distribution channel (51) extending at least part-way around the annular body (40) provides fluid communication between the fluid feed port (47) and the plurality of outlet apertures (50).

Provided is a particulate filter in which a PM collection rate is stably increased. The particulate filter according to the present invention includes a substrate 10 having a wall flow structure having a porous partition wall 16 that partitions an inlet cell and an outlet cell, and a wash coat layer held on surfaces of internal pores of the partition wall. In addition, average filling rates A, B, and C of the wash coat layer measured for each predetermined pore diameter range in the internal pores satisfy specific relationships. Further, the wash coat layer is formed in a region that occupies 50% or more of a thickness of the partition wall, and an amount of a noble metal catalyst carried by the wash coat layer is 0 g/L or more but 0.2 g/L or less.

An electric heating support includes a honeycomb structure having an outer peripheral wall and interior porous partition walls defining a plurality of cells forming a flow path. A pair of electrode layers are disposed on a surface of the outer peripheral wall so as to face each other across a central axis of the honeycomb structure. Protective layers cover the electrode layers, respectively, such that at least a part of each electrode layer is exposed. A pair of metal terminals are provided on the electrode layers. Each electrode layer is composed of a metal-ceramic mixed member. A portion of each electrode layer that is exposed from the protective layer is electrically connected to each of the pair of metal terminals.

Provided is a particulate filter in which a PM collection rate is stably increased. The particulate filter according to the present invention includes a substrate 10 having a wall flow structure having a porous partition wall 16 that partitions an inlet cell and an outlet cell, and a wash coat layer held on surfaces of internal pores of the partition wall. In addition, average filling rates A, B, and C of the wash coat layer measured for each predetermined pore diameter range in the internal pores satisfy specific relationships. Further, the wash coat layer is formed in a region that occupies 50% or more of a thickness of the partition wall, and an amount of a noble metal catalyst carried by the wash coat layer is 0 g/L or more but 0.2 g/L or less.

Described is a method of coating the inside of an exhaust gas purification catalyst filter with a predetermined amount of catalyst slurry while adjusting the distribution of catalyst components in or on a cell wall of the filter. A predetermined amount of catalyst slurry can be injected into an internal channel of a filter to solve conventional problems caused by excess or surplus slurry injection. The predetermined amount of slurry injected into the internal channel of the filter is coated on or in the cell wall, depending on the viscosity and particle size of the slurry. This enables a coating profile in which the slurry distribution at a front portion of the filter and the slurry distribution at a back portion of the filter differ from each other. In addition, the coating profile on the inner surface of the cell wall or in the pores of the cell wall can be adjusted through the subsequent air blowing, so that the back pressure of the filter and the performance of the catalyst filter, such as catalytic activity, can be improved. In addition, the coating length in the filter can be adjusted by controlling the pressure of air during the air blowing.

A Ce—Zr composite oxide contains cerium and zirconium, wherein an uneven distribution ratio of cerium atoms is 1.80 or less. A method for producing a Ce—Zr composite oxide includes an acid treatment step of bringing at least one selected from the group consisting of sulfuric acid, nitric acid, and hydrochloric acid, in an amount of 4 to 28 parts by mass with respect to 100 parts by mass of the raw material composite oxide, into contact with the surface of a raw material composite oxide containing cerium and zirconium, and a calcination step of calcining the treated composite oxide obtained in the acid treatment step at 400 to 1200° C. for 5 to 300 minutes.

A substrate coating apparatus is disclosed. A substrate coating apparatus comprises: a source of a washcoat; a washcoat showerhead for discharging the washcoat towards an upper surface of a substrate; a conduit fluidly connecting the source of the washcoat to the washcoat showerhead for supplying washcoat to the washcoat showerhead; a headset for engaging the substrate to locate the upper surface of the substrate below the washcoat showerhead; and a vacuum generator for drawing the washcoat discharged from the washcoat showerhead through the substrate. The headset comprises a headset seal for engaging against the substrate. The headset seal comprises a perimetral portion that extends around the headset and a cantilevered portion that extends down from the perimetral portion and which is configured to engage against a sidewall of the substrate.

A method of coating a substrate with a washcoat is disclosed. The method comprises engaging the substrate with a headset of a substrate coating apparatus so as to locate an upper surface of the substrate below a washcoat showerhead of the substrate coating apparatus; and discharging a washcoat out of the washcoat showerhead towards the upper surface of the substrate; and drawing the washcoat through the substrate by applying a suction force to a lower surface of the substrate.

A substrate coating apparatus is disclosed. The substrate coating apparatus comprises a substrate holder for holding a substrate vertically; a piston for introducing, by pushing or injecting, a liquid comprising a catalyst component into the substrate via or through open ends of the plurality of channels at a lower end of the substrate; a vacuum generator for applying a vacuum to open ends of the plurality of channels at an upper end of the substrate; and a fluid feed ring for supplying the liquid onto a face of the piston. The fluid feed ring comprises an annular body comprising an inner face bounding a central bore of the fluid feed ring; a fluid feed port for receiving the liquid; a plurality of outlet apertures on the inner face of the annular body for discharging the liquid onto the piston face; and a distribution channel extending at least part-way around the annular body which provides fluid communication between the fluid feed port and the plurality of outlet apertures.

The invention relates to a method for producing a wall-flow filter for removing fine particulate solids from gases, and to the use thereof for cleaning exhaust gases of an internal combustion engine. The invention also relates to a correspondingly produced exhaust-gas filter having a high filtration efficiency.