Abstract: An apparatus for filtering a liquid, with a housing, a liquid inlet arranged in the housing, a liquid outlet arranged in the housing, a filter for removing particles from a liquid stream arranged between the liquid inlet and the liquid outlet, and at least one additive for functionally altering the liquid properties arranged in the apparatus, in which the additive is arranged in the interior volume of the apparatus and is shaped in a colloidally disperse, dimensionally stable, elastic form corresponding to at least one geometric space defined by an interior structure of the apparatus or of the filter for removing the particles.

Abstract: A filter element in which several layers (2, 3, 5, 7, 8) made of a filtering medium are joined contiguously in the direction of flow with at least one layer (2, 7) made of a filtering medium with a high storage capacity and a low degree of separation being arranged on the in-flow side and at least one layer (3, 8) made of a filtering medium with a low storage capacity and a high degree of separation being arranged on the out-flow side. Preferably the in-flow filtering medium is made of a filter paper containing cellulose or of a melt-blown material, and the out-flow side filtering medium is produced from a filter paper containing cellulose.

Abstract: A fuel filter system, particularly a diesel filter, including a housing, a particle filter arranged in the housing, and a coalescer element mounted on the particle filter. Fuel passes successively through the serially connected coalescer and particle filter. The coalescer element improves the separation of any water contained in the fuel to be filtered, while exhibiting no or no significant fuel-filtering properties.

Abstract: A liquid filter, particularly an oil filter for an internal combustion engine, having a housing with an inlet and an outlet and a filter element sealingly arranged between the inlet and the outlet, in which the filter element includes multiple layers at least one of which serves to separate particles from a liquid stream passing through the filter, and another of which is infused with active substances immobilized therein which chemically decompose and/or physically bind contaminants present in the liquid.

Abstract: An apparatus for filtering a liquid, with a housing, a liquid inlet arranged in the housing, a liquid outlet arranged in the housing, a filter for removing particles from a liquid stream arranged between the liquid inlet and the liquid outlet, and at least one additive for functionally altering the liquid properties arranged in the apparatus, in which the additive is arranged in the interior volume of the apparatus and is shaped in a colloidally disperse, dimensionally stable, elastic form corresponding to at least one geometric space defined by an interior structure of the apparatus or of the filter for removing the particles.

Abstract: The invention relates to a multi-layer filter element. The invention provides a main filter layer which preferably consists of a melt-blown fleece and has an absolute filtration capability. A paper layer (2) on the clean side supports the filter element and does not contribute to the filtering of the fluid to be filtered. Said layer can therefore have a macropore structure, thereby allowing a low flow resistance. A layer (3)on the clean side which preferably also consists of paper serves to pre-filter the fluid and to protect and support the main filter layer. The inventive design of the multi-layer filter material provides a means for economically producing filter elements, especially filter cartridges which are folded in the shape of a star, since no trellis protective layers are necessary. The invention also facilitates an improved thermal disposability of the proposed filter cartridge.

Abstract: A multi-layer filter element for filtering fluids, in which a plurality of layers of filter media follow each other in succession in the direction of flow through the filter. All of the individual filter layers are preferably made of synthetic fibers, especially polyester fibers. The successive filter layers exhibit an increasing degree of filter fineness in the direction of flow through the filter, and the filter material contains at least one filter layer arranged on the inflow side of the filter which is composed of a meltblown fiber nonwoven web, especially a polyester fiber web.