Pre-coalescing multi-layered filter media
AssigneeHollingsworth & Vose Company
InventorsMáté Nagy, Siqiang Zhu
Life of this patent
Estimating the term…
Abstract
Fiber webs that may be used as filter media are provided. In some embodiments, the filter media may include multiple layers. Each layer may be designed to have separate functions in the filter media. For example, a first layer may be provided for improving dust holding capacity, a second layer for improving efficiency, and a third layer for providing support and strength to the media. By designing the layers to have separate functions, each layer may be optimized to enhance its function without negatively impacting the performance of another layer of the media.
Claims22
(canceled)
A filter media, comprising:
- a first layer comprising a first plurality of fibers, wherein the first plurality of fibers comprises synthetic fibers, and wherein the first layer has a first air permeability and a first mean flow pore size;
- a second layer comprising a second plurality of fibers, wherein the second plurality of fibers comprises synthetic fibers, and wherein the second layer has a second air permeability and a second mean flow pore size;
- and
- a third layer comprising a third plurality of fibers, wherein the third plurality of fibers comprises synthetic fibers and/or cellulose fibers, and wherein the third layer has a third air permeability and a third mean flow pore size;
- wherein each of the first and third air permeabilities is higher than the second air permeability and/or wherein each of the first and third mean flow pore sizes is higher than the second mean flow pore size;
- wherein the second layer is positioned between the first and third layers;
- wherein the filter media has an efficiency for 4 micron or larger particles of greater than or equal to about 90% measured according to standard ISO 19438;
- and
- wherein the filter media has an initial efficiency for 4 micron or larger particles of greater than or equal to about 80% measured according to standard ISO 19438.
A filter media, comprising:
- a first layer comprising a first plurality of fibers, wherein the first layer has a first air permeability and a first mean flow pore size;
- a second layer comprising a second plurality of fibers, wherein the second layer is a non-wet laid layer, and wherein the second layer has a second air permeability and a second mean flow pore size;
- and
- a third layer comprising a third plurality of fibers, wherein the third layer has a third air permeability and a third mean flow pore size;
- wherein the first layer and/or the third layer comprise cellulose;
- wherein the second layer is positioned between the first and third layers;
- wherein the filter media has an efficiency for 4 micron or larger particles of greater than or equal to about 90% measured according to standard ISO 19438;
- and
- wherein the filter media has an initial efficiency for 4 micron or larger particles of greater than or equal to about 80% measured according to standard ISO 19438.
Dependencies are inferred from the claim text.