Abstract: Filter media comprising nanofibers and related components, systems, and methods associated therewith are provided. In some embodiments, a filter media may comprise a first fiber web and a second fiber web designed to impart beneficial properties to the filter media. For instance, in some embodiments, the first fiber web may provide high particulate efficiency and the second fiber web may provide suitable capacity. In some embodiments, the first and second fiber webs may have certain properties (e.g., water contact angle, surface energy) that are similar or substantially the same. The similarities between the first and second fiber webs may serve to enhance the structural stability of the filter media under various conditions (e.g., high temperature, high pressure, steam sterilization) and/or permeability to certain fluids (e.g., water). Filter media, as described herein, may be particularly well-suited for applications that involve liquid filtration.

Abstract: Filter media comprising a pre-filter layer and related components, systems, and methods associated therewith are provided. In some embodiments, the pre-filter layer may be designed to impart desirable properties to the filter media, such as a high gamma and/or long service life, while having relatively minimal or no adverse effects on another property of the filter media that is important for a given application. For instance, a pre-filter layer may be used to improve the upstream removal of fine particulate matter, which may clog a downstream efficiency layer comprising submicron fibers and reduce filtration performance. The pre-filter layer may be configured to increase service life and/or increase the gamma of the filter media. Filter media, as described herein, may be particularly well-suited for applications that involve filtering air, though the media may also be used in other applications.

Abstract: Filter media comprising a waved filtration layer having a gradient in a property and associated methods are provided. The waved filtration layer may include fibers that form one or more fiber webs. In some embodiments, the diameter of the fibers may vary across at least a portion of the thickness of the waved filtration layer to produce a gradient in fiber diameter. The gradient may be designed to impart beneficial properties to the filter media, such as low pressure drop and long lifetime. In some embodiments, the gradient may be characterized by mathematical equations that describe the change in fiber diameter across at least a portion of the thickness of the waved filtration layer. The filter media, described herein, may be particularly well-suited for applications that involve filtering liquids, though the media may also be used in other applications.

Abstract: Filter media, such as electret-containing filtration media for filtering gas streams (e.g., air), are described herein. In some embodiments, the filter media may be designed to have desirable properties such as stable filtration efficiency over the lifetime of the filter media, increased normalized gamma, relatively low pressure drop (i.e. resistance), and/or relatively low basis weight. In certain embodiments, the filter media may be a composite of two or more types of fiber layers where each layer may be designed to enhance its function without substantially negatively impacting the performance of another layer of the media. For example, one layer of the media may be designed to have a relatively low basis weight and/or a relatively high air permeability, and another layer of the media may be designed to have stable filtration efficiency and/or a relatively high efficiency throughout the filter media's lifetime.

Abstract: Articles and methods involving filter media are generally provided. In certain embodiments, the filter media includes at least a first layer, a second layer, and an adhesive resin positioned between the first layer and the second layer. In some embodiments, the first layer may be a pre-filter layer or a support layer. The second layer may, for example, comprise fibers formed by a solution spinning process and/or may comprise fine fibers. In some embodiments, the adhesive resin may be present in a relatively low amount and/or may have a low glass transition temperature. The filter media as a whole may have one or more advantageous properties, including one or more of a high stiffness, a high bond strength between the first layer and the second layer, a high gamma, and/or a low increase in air resistance after being subjected to an IPA vapor discharge. The filter media may be, for example, a HEPA filter and/or an ULPA filter.

Abstract: Articles and methods relating to filter media are generally provided. In some embodiments, a filter media has an irregular surface structure. For instance, the filter media may comprise a plurality of peaks that are irregular in one or more ways. A ratio of a peak height standard deviation to an average peak height may be greater than or equal to 0.05, and/or a ratio of a peak spacing standard deviation to an average peak spacing may be greater than or equal to 0.08. In some embodiments, a filter media comprises a non-woven fiber web having a layer thickness of greater than 0.3 mm and/or a stiffness of less than or equal to 100 mg.

Abstract: Filter media and related methods of foam forming the filter media are generally described herein.

Abstract: Fine glass fibers, as well as fiber webs, separators, and pasting papers comprising the fine glass fibers, are generally described. In some embodiments, the fine glass fibers have a relatively high BET specific surface area (e.g., greater than or equal to 1.6 m2/g) while maintaining a relatively low aspect ratio (e.g., less than or equal to 80).

Abstract: Filter media comprising surface-treated fiber webs having one or more advantageous physical properties are generally described. Certain improvements in the surface-treated fiber webs described herein may be realized in filter media comprising adsorbent particles. The improvements herein are, in some embodiments, related to favorable distributions of cavities in surface-treated fiber webs, such as those used in backers of the filter media.

Abstract: Filter media comprising surface-treated fiber webs having one or more advantageous physical properties are generally described. Certain improvements in the surface-treated fiber webs described herein may be realized in filter media comprising nanofiber layers. The improvements herein are, in some embodiments, related to favorable distributions of cavities in surface-treated fiber webs, such as those used in backers of the filter media.

Abstract: Filter media comprising a pre-filter layer and related components, systems, and methods associated therewith are provided. In some embodiments, the pre-filter layer may be designed to impart desirable properties to the filter media, such as a high gamma and/or long service life, while having relatively minimal or no adverse effects on another property of the filter media that is important for a given application. For instance, a pre-filter layer may be used to improve the upstream removal of fine particulate matter, which may clog a downstream efficiency layer comprising submicron fibers and reduce filtration performance. The pre-filter layer may be configured to increase service life and/or increase the gamma of the filter media. Filter media, as described herein, may be particularly well-suited for applications that involve filtering air, though the media may also be used in other applications.

Abstract: Articles and methods involving filter media are generally provided. In certain embodiments, the filter media includes at least a first layer, a second layer, and an adhesive resin positioned between the first layer and the second layer. In some embodiments, the first layer may be a pre-filter layer or a support layer. The second layer may, for example, comprise fibers formed by a solution spinning process and/or may comprise fine fibers. In some embodiments, the adhesive resin may be present in a relatively low amount and/or may have a low glass transition temperature. The filter media as a whole may have one or more advantageous properties, including one or more of a high stiffness, a high bond strength between the first layer and the second layer, a high gamma, and/or a low increase in air resistance after being subjected to an IPA vapor discharge. The filter media may be, for example, a HEPA filter and/or an ULPA filter.

Abstract: Articles and methods involving filter media are generally provided. In certain embodiments, the filter media includes at least a first layer, a second layer, and an adhesive resin positioned between the first layer and the second layer. In some embodiments, the first layer may be a pre-filter layer or a support layer. The second layer may, for example, comprise fibers formed by a solution spinning process and/or may comprise fine fibers. In some embodiments, the adhesive resin may be present in a relatively low amount and/or may have a low glass transition temperature. The filter media as a whole may have one or more advantageous properties, including one or more of a high stiffness, a high bond strength between the first layer and the second layer, a high gamma, and/or a low increase in air resistance after being subjected to an IPA vapor discharge. The filter media may be, for example, a HEPA filter and/or an ULPA filter.

Abstract: Articles and methods relating to filter media are generally provided. In some embodiments, a filter media has an irregular surface structure. For instance, the filter media may comprise a plurality of peaks that are irregular in one or more ways. A ratio of a peak height standard deviation to an average peak height may be greater than or equal to 0.05, and/or a ratio of a peak spacing standard deviation to an average peak spacing may be greater than or equal to 0.08. In some embodiments, a filter media comprises a non-woven fiber web having a layer thickness of greater than 0.3 mm and/or a stiffness of less than or equal to 100 mg.

Abstract: Articles and methods relating to filter media are generally provided. In some embodiments, a filter media has an irregular surface structure. For instance, the filter media may comprise a plurality of peaks that are irregular in one or more ways. A ratio of a peak height standard deviation to an average peak height may be greater than or equal to 0.05, and/or a ratio of a peak spacing standard deviation to an average peak spacing may be greater than or equal to 0.08. In some embodiments, a filter media comprises a non-woven fiber web having a layer thickness of greater than 0.3 mm and/or a stiffness of less than or equal to 100 mg.

Abstract: Filter media comprising non-woven fiber webs having high performance are generally described. For instance, in some embodiments, a non-woven fiber web described herein has a relatively high value of gamma and/or a relatively high ratio of dust holding capacity to basis weight. As another example, in some embodiments, a non-woven fiber web described herein is capable of being loaded with dust relatively uniformly throughout its depth. This latter property may assist with increasing the gamma and/or the ratio of dust holding capacity to basis weight.

Abstract: Articles and methods involving filter media are generally provided. In certain embodiments, the filter media includes at least a first layer, a second layer, and an adhesive resin positioned between the first layer and the second layer. In some embodiments, the first layer may be a pre-filter layer or a support layer. The second layer may, for example, comprise fibers formed by a solution spinning process and/or may comprise fine fibers. In some embodiments, the adhesive resin may be present in a relatively low amount and/or may have a low glass transition temperature. The filter media as a whole may have one or more advantageous properties, including one or more of a high stiffness, a high bond strength between the first layer and the second layer, a high gamma, and/or a low increase in air resistance after being subjected to an IPA vapor discharge. The filter media may be, for example, a HEPA filter and/or an ULPA filter.

Abstract: Filter media comprising a pre-filter layer and related components, systems, and methods associated therewith are provided. In some embodiments, the pre-filter layer may be designed to impart desirable properties to the filter media, such as a high gamma and/or long service life, while having relatively minimal or no adverse effects on another property of the filter media that is important for a given application. For instance, a pre-filter layer may be used to improve the upstream removal of fine particulate matter, which may clog a downstream efficiency layer comprising submicron fibers and reduce filtration performance. The pre-filter layer may be configured to increase service life and/or increase the gamma of the filter media. Filter media, as described herein, may be particularly well-suited for applications that involve filtering air, though the media may also be used in other applications.

Abstract: Filter media having a relatively small pore size and related components, systems, and methods associated therewith are provided. The filter media may include a fibrous efficiency layer, a fibrous support layer, and a third layer adjacent to the efficiency layer. The efficiency layer may impart a relatively homogeneous pore structure to the filter media without adding substantial bulk to the filter media. The support layer may promote the homogeneity of the pore structure. For example, the support layer may prevent and/or minimize defects in the relatively thin efficiency layer that may result from manufacturing and/or processing. The third layer may serve to impart beneficial filtration (e.g., efficiency, dust holding capacity) and/or non-filtration (e.g., layer protection) properties to the filter media without adversely affecting one or more properties of the filter media.

Abstract: Filter media comprising a pre-filter layer and related components, systems, and methods associated therewith are provided. In some embodiments, the pre-filter layer may be designed to impart desirable properties to the filter media, such as a high gamma and/or long service life, while having relatively minimal or no adverse effects on another property of the filter media that is important for a given application. For instance, a pre-filter layer may be used to improve the upstream removal of fine particulate matter, which may clog a downstream efficiency layer comprising submicron fibers and reduce filtration performance. The pre-filter layer may be configured to increase service life and/or increase the gamma of the filter media. Filter media, as described herein, may be particularly well-suited for applications that involve filtering air, though the media may also be used in other applications.