Abstract: A filter medium comprising a first conductive fibrous substrate, a second conductive fibrous substrate spaced apart from the first conductive substrate and a third insulation substrate fitted between the first and the second substrates for electrically separating the first conductive substrate from the second conductive substrate. The first conductive fibrous substrate comprises a first layer with first fibers having a first average diameter; a second layer with second fibers having a second average diameter; and a third layer with third fibers having a third average diameter. The second layer comprises activated carbon in an amount sufficient to render the first fibrous substrate conductive. The present medium can be used in electrified filters for cabin air filtration for passenger cars and other vehicles. It can also be used for HVAC filtration for indoor air, and in portable air purification units and even in vacuum cleaners.

Abstract: The present invention relates to a filter medium being at least formed of a pre-filter substrate laminated with a fine-filter substrate by means of a third binder, wherein the pre-filter substrate comprises synthetic fibers and a first binder, the pre-filter substrate working as a combined surface and depth filter, and the fine-filter substrate comprises at least a second binder and one of synthetic fibers and inorganic fibers.

Abstract: The present invention relates to a filter medium being at least formed of a pre-filter sub-strate laminated with a fine-filter substrate by means of a third binder, wherein the pre-filter substrate comprises synthetic fibers and a first binder, the pre-filter substrate work-ing as a combined surface and depth filter, and the fine-filter substrate comprises at least a second binder and one of synthetic fibers and inorganic fibers.

Abstract: The present invention relates to a filter medium being at least formed of a pre-filter substrate laminated with a fine-filter substrate by means of a third binder, wherein the pre-filter substrate comprises synthetic fibers and a first binder, the pre-filter substrate working as a combined surface and depth filter, and the fine-filter substrate comprises at least a second binder and one of synthetic fibers and inorganic fibers.

Abstract: A filter medium comprising a first conductive fibrous substrate, a second conductive fibrous substrate spaced apart from the first conductive substrate and a third insulation substrate fitted between the first and the second substrates for electrically separating the first conductive substrate from the second conductive substrate. The first conductive fibrous substrate comprises a first layer with first fibers having a first average diameter; a second layer with second fibers having a second average diameter; and a third layer with third fibers having a third average diameter. The second layer comprises activated carbon in an amount sufficient to render the first fibrous substrate conductive. The present medium can be used in electrified filters for cabin air filtration for passenger cars and other vehicles. It can also be used for HVAC filtration for indoor air, and in portable air purification units and even in vacuum cleaners.