Abstract: This disclosure describes filter media and mask filters and face mask systems including those filter media. In one aspect, the filter media includes a fibrous media including multi-component binder fibers, glass fibers, and microfibrillated cellulose fibers. In some aspects, the fibrous media further includes PET fibers. In another aspect, the filter media includes an electrostatically charged filter media, a fine fiber layer, and a scrim. In yet another aspect, the filter media includes two fine fiber layers, and two scrims. In additional aspects, the filter media includes bicomponent fibers, polyethylene terephthalate fibers, and microfibrillated cellulose fibers. In a further aspect, the filter media includes a support layer, a continuous fine fiber layer, and an efficiency layer. Combinations and composites of the filter media are also contemplated.

Abstract: A composite media includes a stack with 20 or more layers, each layer including a substrate with a first major surface and an opposing second major surface; and a fiber layer deposited onto the first major surface of the substrate and including polymeric fibers with a diameter of 100 nm to 1.5 ?m. Each fiber layer independently has a thickness of 5 ?m to 100 ?m, and each layer independently has a pore size of 0.1 ?m to 10 ?m. A filter may include a housing and the composite media disposed within the housing. The filter may be a syringe filter.

Abstract: This disclosure describes a filtration composite that includes multiple layers of filtration media. In some embodiment, the filtration composite is preferably substantially glass-free or glass-free. When the composite is glass-free or substantially glass-free, the composite preferably exhibits capacity and efficiency comparable to or better than similar glass-containing filtration media. The composite includes a first nonwoven filtration medium including bicomponent fibers, efficiency fibers having a fiber diameter in a range of 1 micron to 5 microns, and microfibrillated fiber; an optional second nonwoven filtration medium; and a third nonwoven filtration medium including efficiency fibers having a fiber diameter of at least 0.1 micron and less than 1 micron.

Abstract: This disclosure describes a filtration medium that is preferably glass-free or substantially glass-free. In some embodiments, the filtration medium preferably exhibits capacity and efficiency comparable to or better than similar glass-containing filtration media. The filtration medium includes bicomponent fibers, efficiency fibers (for example, PET fibers), and microfibrillated fibers. The efficiency fibers include fibers having a fiber diameter in a range of 1 micron to 5 microns and fibers having a fiber diameter of at least 0.1 micron and less than 1 micron.

Abstract: This disclosure describes a high performing (including, for example, high efficiency and low pressure drop) filter media. The filter media includes a support layer and a layer of fine fibers wherein at least some of the fine fibers in the fine fiber layer having an average diameter at least 3 times the average fiber diameter of a smaller fine fiber in the fine fiber layer. The fine fiber layer may include multiple layers of fine fibers. In some aspects, the smaller fine fiber may be present in the same layer of fine fibers as the larger fine fibers. Additionally or alternatively, the larger fine fibers may be present in a first layer of fine fibers and the smaller fine fibers may be present in a second layer of fine fibers.

Abstract: This disclosure describes a filter medium that minimizes the adverse effects of variations in flow rate on filter medium efficiency without a corresponding increase in pressure drop. The filter medium includes a support layer, a continuous fine fiber layer, and an efficiency layer. The continuous fine fiber layer includes a continuous fine fiber that has a diameter of up to 10 micrometers and is located downstream of the efficiency layer.

Abstract: The cyclic flow apparatuses consistent with the technology disclosed herein are configured to sealably couple to a liquid flow circuit. The cyclic flow apparatus is configured to change a flow velocity of a liquid through a filter media holder. In various embodiments, the cyclic flow apparatus is configured to change the flow velocity of the liquid through a portion of the liquid flow circuit. The cyclic flow apparatus can be configured to cyclically change the flow velocity of the liquid in the liquid flow circuit through the filter media holder.