Filter media with a multi-layer structure

Patent metadata

Field	Value
Publication number	US-2016184751-A1
Application number	US-201514984406-A
Country	US
Kind code	A1
Filing date	Dec 30, 2015
Priority date	Apr 27, 2010
Publication date	Jun 30, 2016
Grant date	—

Abstract

Filter media are described. The filter media may include multiple layers. In some embodiments, the filter media include a nanofiber layer adhered to another layer. In some embodiments, the layer to which the nanofiber layer is adhered is formed of multiple fiber types (e.g., fibers that give rise to structures having different air permeabilities and/or pressure drops). In some embodiments, the nanofiber layer is adhered to a single-phase or a multi-phase layer. In some embodiments, the nanofiber layer is manufactured from a meltblown process. The filter media may be designed to have advantageous properties including, in some cases, a high dust particle capture efficiency and/or a high dust holding capacity.

First claim

1 . A filter media comprising:
a first layer comprising: a first phase including a first plurality of fibers and a second plurality of fibers different from the first plurality of fibers; a second phase including a third plurality of fibers and a fourth plurality of fibers different from the third plurality of fibers, the third plurality of fibers being the same as or different from the first or second plurality of fibers and the fourth plurality of fibers being the same as or different from the first or second plurality of fibers, wherein the air permeability of the first plurality of fibers is greater than the air permeability of the second plurality of fibers, wherein the air permeability of the third plurality of fibers is greater than the air permeability of the fourth plurality of fibers; and a second layer attached to the first layer, wherein the second layer is a nanofiber layer, and wherein the nanofiber layer has an average fiber diameter of from 0.1 microns to 1.5 microns.

2 . The filter media of claim 1 , wherein the first layer includes a polyester fiber having a denier of between 3.0 and 6.0.

3 . The filter media of claim 1 , wherein the second layer comprises a meltblown material.

4 . The filter media of claim 3 , wherein the meltblown material includes at least one of polybutylene terephthalate fibers, polypropylene fibers, nylon, or thermoplastic polyurethane.

5 . The filter media of claim 1 , wherein the filter media has a permeability of between 75 CFM and 250 CFM.

6 . The filter media of claim 1 , wherein the first, second, third or fourth plurality of fibers have an average fiber length from 1.5 mm to 6 mm.

7 . The filter media of claim 1 , wherein the first or third plurality of fibers comprise softwood fibers, cotton fibers, polyester fibers, polyvinyl alcohol binder fibers, or rayon fibers, and the second or fourth plurality of fibers comprise hardwood fibers, polyethylene fibers, or polypropylene fibers.

8 . The filter media of claim 7 , wherein the first or third plurality of fibers comprise hardwood or softwood fibers.

9 . The filter media of claim 1 , wherein the first phase has a higher air permeability than the second phase, and/or the first layer has a higher air permeability than the nanofiber layer.

10 . The filter media of claim 1 , wherein the filter media has a mean flow pore size from 5 microns to 50 microns, and/or the nanofiber layer is a meltblown layer having a mean flow pore size of between 5 microns and 50 microns.

11 . The filter media of claim 1 , wherein the first layer has an air permeability between 2 CFM and 250 CFM.

13 . The filter media of claim 1 , wherein fibers of the nanofiber layer have a diameter of 0.2 to 0.8 microns.

14 . The filter media of claim 1 , wherein the first layer has an initial dust capture efficiency of at least 60% as measured by a Palas flat sheet test involving challenging a 100 cm 2 surface area of the first layer with fine dust particles (0.1-80 μm) at a concentration of 200 mg/m 3 with a face velocity of 20 cm/s for one minute.

15 . The filter media of claim 1 , wherein the filter media has a thickness of between 700 microns and 1.5 mm.

16 . The filter media of claim 1 , wherein the filter media has a basis weight of between 50 g/m 2 and 200 g/m 2 , and/or wherein the nanofiber layer is a meltblown layer having a basis weight of from 2 g/m 2 to 20 g/m 2 .

17 . The filter media of claim 1 , wherein the filter media has an air permeability of greater than 10 CFM and at most 200 CFM.

18 . The filter media of claim 1 , wherein the nanofiber layer is a meltblown layer having a thickness of at least 5 microns and at most 500 microns.

19 . The filter media of claim 1 , wherein the first or third pluralities of fibers are made from an organic polymeric material.

20 . The filter media of claim 1 , wherein a weight ratio of the first plurality of fibers to the second plurality of fibers in the article is from 50:50 to 97:3.

Assignees

• Hollingsworth & Vose Co

Inventors

• Wertz John A
• Guimond Douglas M

Classifications

• B01D39/163 Primary

  sintered or bonded · CPC title

• B01D39/1615

  of natural origin · CPC title

• B01D46/546

  using nano- or microfibres · CPC title

• Y10T442/659

  Including an additional nonwoven fabric · CPC title

• B01D2239/025

  comprising nanofibres · CPC title