Filter media including a filtration layer comprising fibers (e.g., synthetic fibers) comprising a flame retardant and related components, systems, and methods associated herewith are provided. In some embodiments, a filtration layer may include a nonwoven web (e.g., wet-laid nonwoven web) comprising fibers including a certain flame retardant that has a relatively low concentration of or is substantially free of certain undesirable and/or toxic components (e.g., halogens). In certain embodiments, the nonwoven web may also comprise a blend of fibers. For instance, in some embodiments, the nonwoven web may also comprise a blend of coarse and fine diameter synthetic fibers that impart beneficial performance properties to the filtration layer. In some embodiments, the filtration layer may be designed to have a desirable flame retardancy (e.g., F1 rating, K1 rating) and performance properties without compromising certain mechanical properties (e.g., pleatability of the media) and/or environmental attributes (e.g., relatively low toxicity). Filter media described herein may be particularly well-suited for applications that involve filtering air, though the media may also be used in other applications.

The present invention provides a process for preparing a functionalised polymeric chromatography medium, which process comprises (I) providing two or more non-woven sheets stacked one on top of the other, each said sheet comprising one or more polymer nanofibres, (II) simultaneously heating and pressing the stack of sheets to fuse points of contact between the nanofibres of adjacent sheets, and (III) contacting the pressed and heated product with a reagent which functionalises the product of step (II) as a chromatography medium.

The present invention provides a process for preparing a functionalised polymeric chromatography medium, which process comprises (I) providing two or more non-woven sheets stacked one on top of the other, each said sheet comprising one or more polymer nanofibres, (II) simultaneously heating and pressing the stack of sheets to fuse points of contact between the nanofibres of adjacent sheets, and (III) contacting the pressed and heated product with a reagent which functionalises the product of step (II) as a chromatography medium.

Filter media having a gradient in a property and methods associated with such media are provided. In some embodiments, a filter media may have a gradient in mean pore size. The gradient in mean pore size may be across at least a portion of the thickness of the filter media. In some embodiments, the gradient can be represented by an exponential function. The exponential gradient in mean pore size may impart desirable properties to the filter media including enhanced filtration properties (e.g., relatively high dust holding capacity and efficiency), amongst other benefits. The filter media may be particularly well-suited for applications that involve filtering liquids (e.g., hydraulics, fuel, lube, water), though the media may also be used in other applications.

Filter media having a gradient in a property and methods associated with such media are provided. In some embodiments, a filter media may have a gradient in mean pore size. The gradient in mean pore size may be across at least a portion of the thickness of the filter media. In some embodiments, the gradient can be represented by an exponential function. The exponential gradient in mean pore size may impart desirable properties to the filter media including enhanced filtration properties (e.g., relatively high dust holding capacity and efficiency), amongst other benefits. The filter media may be particularly well-suited for applications that involve filtering liquids (e.g., hydraulics, fuel, lube, water), though the media may also be used in other applications.

Various embodiments of a filter cartridge are disclosed. The filter cartridge includes a first filter media layer having first and second major surfaces, a second filter media layer having first and second major surfaces, and a plenum disposed between the first and second filter media layers. The filter cartridge further includes functional material disposed on the first major surface of each of the first and second filter media layers within a filter region of the filter cartridge, where the functional material includes active particles disposed on an adhesive layer; and a perimeter seal region that defines at least a portion of a perimeter of the filter cartridge, where at least the first and second filter media layers are connected together in the perimeter seal region. The functional material is not disposed in at least a portion of the perimeter seal region.

Various embodiments of a filter cartridge are disclosed. The filter cartridge includes a first filter media layer having first and second major surfaces, a second filter media layer having first and second major surfaces, and a plenum disposed between the first and second filter media layers. The filter cartridge further includes functional material disposed on the first major surface of each of the first and second filter media layers within a filter region of the filter cartridge, where the functional material includes active particles disposed on an adhesive layer; and a perimeter seal region that defines at least a portion of a perimeter of the filter cartridge, where at least the first and second filter media layers are connected together in the perimeter seal region. The functional material is not disposed in at least a portion of the perimeter seal region.

The invention relates to a method for producing a filter device (1) for filtering a hydrophilic liquid, comprising a flat filter element (10) which is permeable to the liquid, wherein the filter element (10) has a delimited filter region (11) which is coated with a hydrophobic agent. The following steps are carried out: a) providing the flat filter element (10) which has in particular a nonwoven filter web (13) lying between a mesh support layer (14) and a spun-bonded fabric (15), b) producing a compressed annular boundary region (16) for the filter region (11), c) applying the agent onto the filter region (11) of the filter element (10), and d) obtaining the filter device (1).

The invention relates to a method for producing a filter device (1) for filtering a hydrophilic liquid, comprising a flat filter element (10) which is permeable to the liquid, wherein the filter element (10) has a delimited filter region (11) which is coated with a hydrophobic agent. The following steps are carried out: a) providing the flat filter element (10) which has in particular a nonwoven filter web (13) lying between a mesh support layer (14) and a spun-bonded fabric (15), b) producing a compressed annular boundary region (16) for the filter region (11), c) applying the agent onto the filter region (11) of the filter element (10), and d) obtaining the filter device (1).

A mouth-nose mask for reducing the transmission of pathogens via droplets of secretion is disclosed. The mouth-nose mask includes a central fold which defines a chin-nose line of the mouth-nose mask and separates the mouth-nose mask into two substantially congruent halves. A fastening means for fastening the mouth-nose mask to a wearer's ears or back of the head is attached to the ends of the two halves remote from the central fold. The mouth-nose mask includes at least two superposed layers of a filter material, the at least two layers defining the outer shape of the mouth-nose mask and being only partially joined to one another at their edges.