Disclosed are processes for producing molded polyurethane elastomers and products, such as filter end caps, that include such elastomers. The elastomers are the reaction product of a non-foaming reaction mixture comprising an isocyanate-reactive composition and an organic polyisocyanate prepolymer with an internal mold release agent.

A liquid filter cartridge is provided. Preferred seal arrangements are provided, to provide for preferred axial load conditions, with respect to one or more of the end caps of the cartridge. Some cartridge configurations provided include no core structure or outer liner structure therein, to support axial load. Assemblies using the cartridge, and methods of assembly and use, are provided. The liquid filter cartridge can be a serviceable cartridge, or it can be retained permanently in a housing.

A liquid filter cartridge is provided. Preferred seal arrangements are provided, to provide for preferred axial load conditions, with respect to one or more of the end caps of the cartridge. Some cartridge configurations provided include no core structure or outer liner structure therein, to support axial load. Assemblies using the cartridge, and methods of assembly and use, are provided. The liquid filter cartridge can be a serviceable cartridge, or it can be retained permanently in a housing.

A method includes providing a computer-readable three-dimensional model of a filter medium including a plurality of segments, each segment of the three-dimensional model being configured to be converted into a plurality of slices that each define a cross-sectional layer of the filter medium, the filter medium including a first end defining a first cavity that extends from the first end along a predetermined direction that defines an undercut along the first predetermined direction; and successively forming each layer of the filter medium by additive manufacturing.

A filter center tube includes a plurality of layers of solidified material including a first layer with a first undulating strip of solidified material extending in a first predetermined direction, and a second layer with a second undulating strip of solidified material extending in a second predetermined direction. The first layer is in contact with the second layer and the first predetermined direction is not parallel with the second predetermined direction, forming a plurality of pores therebetween.

The inventive semi-finished product for a filter, particularly an air filter, comprises a filter medium, wherein said filter medium comprises a nonwoven having fibrous structure produced in a melt-spinning process and at least partially arranged in pleated layers.

Support and drainage materials, filter including the materials, and methods of use are disclosed.

Support and drainage materials, filter including the materials, and methods of use are disclosed.

Support and drainage materials, filter including the materials, and methods of use are disclosed.

Support and drainage materials, filter including the materials, and methods of use are disclosed.