A water-treating ceramic filter unit comprising a filter having pluralities of flow paths partitioned by porous ceramic cell walls and plugs alternately sealing the one-side or other-side ends of the flow paths; a housing containing the filter such that water to be treated is supplied from one end of the filter, and that the treated water is discharged from the other end of the filter; and seal members disposed on the outer edge portions of both end surfaces of the filter for longitudinally sandwiching and fixing the filter to the housing; the maximum of a gap between a side surface of the filter and the housing being equal to or less than the equivalent diameter of the flow paths.

A high pressure filter including first and second housings having complimentary tapered surfaces, a gasket located between the tapered surfaces, a filter element centrally disposed within the housings, and a compression collar fitted over the second housing and threaded onto the first housing is provided. Methods of making and using high pressure filters are also provided.

A particulate filter 23 is configured by being provided with, arranged side by side, a plurality of honeycomb-shaped segments 29, 30, 31 having a plurality of cells 32. The density of cells in the segments 30, 31 disposed in the outer circumference part is set to be lower than the density of cells in the segments 29 disposed in the center part. In addition, the segments 30, 31 disposed in the outer circumference part are configured so that the density of the cells 32 becomes lower as the area of the end face becomes smaller.

A ceramic honeycomb filter comprising a cordierite-type ceramic honeycomb structure having large numbers of flow paths partitioned by porous cell walls, and plugs formed in end portions of predetermined flow paths of the ceramic honeycomb structure; the cell walls having a thermal expansion coefficient Tw (×10.sup.−7/° C.) of 10 or less in the flow path direction between 40° C. and 800° C.; the plugs comprising at least ceramic particles, and 5-25 parts by mass of an amorphous oxide matrix per 100 parts by mass of the ceramic particles; the ceramic particles comprising at least 42-90% by mass of amorphous silica particles, and 10-58% by mass of cordierite particles; and the amorphous silica particles comprising 4-30% by mass of first silica particles having a median particle diameter of 10-40 μm, and 70-96% by mass of second silica particles having a median particle diameter of 70-200 μm.

A filter to remove contaminants from potable water. The filter comprises a plurality of porous layers 15,16 forming a fluid path for the water to pass sequentially from the first layer 16 through the layers to the final layer. The first layer 16 is formed of a ceramic and/or sintered material and includes a virucide. Said first layer 16 is distinguishable from an adjacent second layer 15, wherein at least one of the first and second layers 16, 15 comprises a dye material.

An outer periphery coating material being coated onto an outer peripheral surface of a ceramic honeycomb structure to form an outer periphery coated layer. The outer periphery coating material comprises: a particle mixture containing cordierite particles and amorphous silica particles in a mass ratio of from 40:60 to 80:20; and from 10 to 30% by mass of crystalline inorganic fibers in an outer percentage relative to the particle mixture. An average particle diameter of the cordierite particles is different from an average particle diameter of the amorphous silica particles.

Aspects of the disclosure provide methods of making a coated filtration material. Various methods include providing a base filter material and applying a first coating to the base filter material, the first coating being in nanoparticle form. A second coating is applied on top of the first coating, the second coating being a nanoscale inorganic material. The method further includes removing the first coating in such a way that the second coating remains on the base filter material. Methods of the disclosure can be used to manufacture coated filtration materials having a coating with a porosity of 90% or greater and a pore size in the range of 0.1-0.5 μm.

In order to enable stable provision of an upward release tube-type ceramic filter used in a molten metal bath and having a side wall with a height of 300 mm or greater, this method for manufacturing a ceramic filter, which is an upward release tube-type integrally molded article for removing unwanted substances from molten metal, has: a step for kneading a mixture of an aggregate comprising ceramic particles, a prescribed binding agent, and water to prepare a base material; a step for integrally forming an upward release tube-type ceramic filter precursor from the prepared base material; step for drying the precursor; a step for providing a retainer for the dried precursor for supporting a side wall of the precursor; a step for subsequently sintering the precursor; and a step for removing the retainer after sintering.

A particulate filter 23 is configured by being provided with, arranged side by side, a plurality of honeycomb-shaped segments 29, 30, 31 having a plurality of cells 32. The density of cells in the segments 30, 31 disposed in the outer circumference part is set to be lower than the density of cells in the segments 29 disposed in the center part. In addition, the segments 30, 31 disposed in the outer circumference part are configured so that the density of the cells 32 becomes lower as the area of the end face becomes smaller.

A water-treating ceramic filter unit comprising a filter having pluralities of flow paths partitioned by porous ceramic cell walls and plugs alternately sealing the one-side or other-side ends of the flow paths; a housing containing the filter such that water to be treated is supplied from one end of the filter, and that the treated water is discharged from the other end of the filter; and seal members disposed on the outer edge portions of both end surfaces of the filter for longitudinally sandwiching and fixing the filter to the housing; the maximum of a gap between a side surface of the filter and the housing being equal to or less than the equivalent diameter of the flow paths.