Granted Patent B2

US 12,274,968 · App. 18/663,367 · Granted Apr 15, 2025

Inventors: Sudhakar Jaganathan (Northborough, MA); Nagendra Anantharamaiah (Acton, MA); Maxim Silin (Hudson, MA)

Assignee: Hollingsworth & Vose Company

B01D46/62A41D13/11B01D39/1623B01D39/1692B01D46/521B01D46/543A62B23/02A62B23/025B01D2239/0622B01D2239/0631B01D2239/065B01D2239/1233B01D2275/10

Abstract

Claims (31)

1. A filter media, comprising:

a first layer comprising first fibers, wherein the first fibers comprise synthetic fibers, wherein the synthetic fibers have a median diameter of less than or equal to 4 microns, wherein the first layer has a thickness of greater than or equal to 20 microns, wherein the first layer has an initial DOP efficiency of less than or equal to 90% when in an uncharged state, and wherein the first layer has an air permeability of greater than or equal to 10 CFM and less than or equal to 750 CFM;

a second layer comprising second fibers having a median diameter of less than or equal to 1 micron, wherein the second layer has an initial DOP efficiency of greater than or equal to 60% and wherein the initial DOP efficiency of the second layer is greater than the first layer when the first layer is in an uncharged state; and

a third layer, wherein the third layer has an air permeability of greater than or equal to 75 CFM.

2. The filter media of claim 1 , wherein the filter media comprises less than 1 wt % glass fibers.

3. The filter media of claim 1 , wherein the filter media has 0 wt % glass fibers.

4. The filter media of claim 1 , wherein the third layer is a backer layer.

5. The filter media of claim 1 , wherein the first layer has a thickness of less than or equal to 2 mm.

6. The filter media of claim 1 , wherein the first layer has a thickness of less than or equal to 1 mm.

7. The filter media of claim 1 , wherein the first layer has a basis weight of less than or equal to 30 g/m 2 .

8. The filter media of claim 1 , wherein the first fibers have a median diameter of less than or equal to 1 micron.

9. The filter media as in claim 1 , wherein the synthetic fibers comprise meltblown fibers.

10. The filter media as in claim 1 , wherein the second fibers comprise electrospun fibers.

11. The filter media of claim 1 , wherein the synthetic fibers have a median fiber diameter of greater than or equal to 0.5 microns and less than or equal to 2 microns.

12. The filter media as in claim 1 , wherein a surface area of the first layer is less than or equal to 3 m 2 /g.

13. The filter media as in claim 1 , wherein the initial DOP efficiency of the first layer is greater than or equal to 30% and less than or equal to 80% when in an uncharged state.

14. The filter media as in claim 1 , wherein the median fiber diameter of the second fibers is less than or equal to 0.2 microns.

15. The filter media as in claim 1 , wherein the third layer has an air permeability of greater than or equal to 75 CFM and less than or equal to 2,000 CFM.

16. The filter media as in claim 1 , wherein the first layer is a pre-filter layer.

17. A method comprising filtering a fluid using the filter media of claim 1 .

18. The filter media as in claim 1 , wherein the first fibers have a median diameter of less than or equal to 2 microns.

19. The filter media as in claim 1 , wherein:

the first fibers comprise meltblown fibers;

the second fibers comprise electrospun fibers;

the third layer has the air permeability of greater than or equal to 75 CFM and less than or equal to 2,000 CFM; and

the filter media has 0 wt % glass fibers.

20. The filter media as in claim 19 , wherein:

the first layer is a pre-filter layer;

the third layer is a backer layer;

the first layer has the thickness of less than or equal to 1 mm; and

the first layer has a basis weight of less than or equal to 30 g/m 2 .

Assignments (2)

Continuity (5)

References Cited (276)