A support structure for an interior volume of a construction of pleated media is operably oriented in the interior volume and structurally supports the media. The support structure can pass directly through an innermost 60% of the interior volume. It can have a void volume not more than 80%. It can be inner liner-free and extend in a non-curved path. It can include a first sheet and second sheet of porous material. At least a first brace construction secures the first sheet and second sheet together and in spaced apart, opposing relation. The support structure can include a pleated construction having pleats extending in a direction non-parallel and angled to the direction of pleats of the pleated filter media. The support structure can be molded spacers.

A filter assembly comprises a filter housing defining an internal volume, a filter element positioned within the internal volume, and a gasket retainer. An outer edge of the gasket retainer is coupled to a top end of the filter housing, and an inner rim thereof forms a gasket retainer ledge. The filter assembly further comprises a retainer loop comprising a retainer loop main body. A plurality of retainer arms extend axially from the retainer loop main body towards the gasket retainer. Each of the plurality of retainer arms comprise a retainer arm ledge extending radially towards the retainer loop main body and snap-fit to the gasket retainer ledge. A retainer loop sidewall extends from the main body away from the gasket retainer. An outer surface of the retainer loop sidewall defines a curvature. A sealing member is removably positioned around the outer surface of the retainer loop sidewall.

A method of packaging a filter media that is pre-folded for insertion is a filter assembly is provided.

A filter device provides for designs that permit variable levels of solid particle and water molecule removal. The filter device retains the particles and the water molecules in the filter medium when removed, thus avoiding the re-entry of the particles and water molecules when the power system has cooled down as is now likely in conventional filters currently in use. Further, the filter device traps the water molecules already present in the fluid being filtered (i.e., “native water”), as well as any moisture resulting from condensation that may be introduced into the lubrication system whenever it is opened.

Provided are certain composite membranes useful for removing various impurities from liquids. In certain aspects, the composite membranes comprise a hydrophobic polymer having a polyamide coated thereon, and in other aspects, such composite membranes having certain acrylic polymers coated thereon. The composite membranes are useful in the removal of various impurities in liquids, such as those encountered in industrial and life sciences processes.

A tetrafluoroethylene polymer is provided in an air filter medium having a pressure loss that can be reduced and made uniform at a plurality of positions. The tetrafluoroethylene polymer may also be provided in an air filter medium, a filter pack, or an air filter unit. The tetrafluoroethylene polymer has drawability and non-melt processability. The tetrafluoroethylene polymer has a ratio S.sub.2/S.sub.1 of 0.60 or more, where S.sub.2 represents an endotherm mJ/mg in a range of T.sub.0° C. or higher and 350° C. or lower, T.sub.0° C. is a temperature 2.5° C. lower than a temperature T.sub.p° C. (340≤T.sub.p≤345) at which a minimum point is given on a heat-of-fusion curve obtained by measuring an unbaked polymer for measurement having no history of heating to a temperature of 300° C. or higher using a differential scanning calorimeter at a temperature-increasing rate of 2° C./min, and S.sub.1 represents an endotherm mJ/mg in a range of 320° C. or higher and T.sub.0° C. or lower.

A fluid purification system can include a filter comprising photocatalytic material, a light source configured to illuminate the photocatalytic material, and a scattering film configured to scatter light emitted from the light source.

A rechargeable spin-on filter includes a cover, a housing threadably joined with the housing, and a filter element can be replaced with another filter element relative thereto. The cover and/or housing can be plastic. The cover can include a bottom plate having inlet ports and an outlet port. The bottom plate can be reinforced with an optionally metal reinforcing plate that registers and locks relative to the bottom plate via locking elements, in the form of corresponding apertures and projections or tabs that interfit with one another. A related method is provided.

A rechargeable spin-on filter includes a cover, a housing threadably joined with the housing, and a filter element that can be removed and replaced with another filter element relative thereto. The cover and/or housing can be plastic. The cover can include a bottom plate having inlet ports and an outlet port. The filter element can include an end cap defining a perimeter about an inner dimension, such as an inner diameter. The cap can define a groove to receive a rib of a support tube over which the element is installed. Alignment of the rib and groove can index and register the element with the support tube. A related method is provided.

A filter media, filter element, filter system and methods are provided. The filter media provides improved filter characteristics including water separation efficiency. The filter media may include one or more of increased surface roughness and/or embossments. The filter media may be provided by pleated filter media.