Meltblown filter medium, related applications and uses

Patent metadata

Field	Value
Publication number	US-8986432-B2
Application number	US-49658809-A
Country	US
Kind code	B2
Filing date	Jul 1, 2009
Priority date	Nov 9, 2007
Publication date	Mar 24, 2015
Grant date	Mar 24, 2015

Abstract

Filter media, as well as related assemblies, systems and methods. Filter media may contain one or more layers formed of a meltblown material.

First claim

The invention claimed is:

1. A filter element, comprising:
an inlet;
an outlet;
a filter medium positioned between the inlet and the outlet, the filter medium comprising:
a first substrate layer facing the inlet, the substrate layer having an air permeability of at least 70 CFM and at most 400 CFM, and a thickness of at least 400 microns and at most 1500 microns;
a second layer positioned downstream of the first substrate layer, wherein the second layer has a thickness of at least 5 microns and at most 30 microns, and wherein the second layer comprises meltblown fibers having an average diameter of at least 0.2 microns and at most 1.5 microns; and
a third layer comprising an adhesive material between and adhering the first and second layers, wherein the third layer has a basis weight of from 0.5 g/m 2 to 10 g/m 2 .

2. The filter element of claim 1 , wherein the first substrate layer has an air permeability of between 100 CFM and 300 CFM.

3. The filter element of claim 1 , wherein the first substrate layer has an air permeability of between 160 CFM and 200 CFM.

4. The filter element of claim 1 , wherein the first substrate layer has a basis weight of at least 75 g/m 2 and at most 500 g/m 2 .

5. The filter element of claim 1 , wherein the second layer comprises meltblown fibers having an average diameter of at least 0.2 microns and at most 0.8 microns.

6. The filter element of claim 1 , wherein the second layer comprises meltblown fibers having an average diameter of at least 0.2 microns and at most 0.6 microns.

7. The filter element of claim 1 , wherein the filter medium is substantially free of an oil coating.

8. The filter element of claim 1 , wherein the filter medium has a dust holding capacity of at least 150 g/m 2 and at most 250 g/m 2 .

9. The filter element of claim 1 , wherein the filter medium has a dust holding capacity of at least 200 g/m 2 and at most 250 g/m 2 .

10. The filter element of claim 1 , wherein the filter medium has an air permeability of from 100 to 200 CFM.

11. The filter element of claim 1 , wherein the filter medium has an initial dust capture efficiency of at least 90% for 10 micron particles.

12. The filter element of claim 1 , wherein the filter medium has an initial dust capture efficiency of at least 95% for 20 micron particles.

13. The filter element of claim 1 , wherein the filter element is an automotive air filter.

14. The filter element of claim 1 , wherein the first substrate layer comprises an organic polymer.

15. A method of filtering a fluid, comprising:
passing a fluid across a filter medium comprising:
a first, uppermost layer comprising a substrate having an air permeability of at least 70 CFM and at most 400 CFM, and a thickness of at least 400 microns and at most 1500 microns;
a second layer positioned downstream of the first, uppermost layer, wherein the second layer has a thickness of at least 5 microns and at most 30 microns, and wherein the second layer comprises meltblown fibers having an average diameter of at least 0.2 microns and at most 1.5 microns; and
a third layer comprising an adhesive material between and adhering the first and second layers, wherein the adhesive material is constructed and arranged to adhere the first layer to the second layer and to permit fluid to pass through the third layer, and wherein the third layer has a basis weight of from 0.5 g/m 2 to 10 g/m 2 .

16. The method of claim 15 , wherein the first, uppermost layer has an air permeability of between 160 CFM and 200 CFM.

17. The method of claim 15 , wherein the first, uppermost layer has a basis weight of at least 75 g/m 2 and at most 500 g/m 2 .

18. The method of claim 15 , wherein the second layer comprises meltblown fibers having an average diameter of at least 0.2 microns and at most 0.8 microns.

19. The method of claim 15 , wherein the filter medium has a dust holding capacity of at least 200 g/m 2 and at most 250 g/m 2 .

20. The method of claim 15 , wherein the filter medium has an air permeability of from 100 to 200 CFM.

21. The method of claim 15 , wherein the fluid is automotive air.

22. The method of claim 15 , wherein the first layer comprises an organic polymer.

23. The method of claim 15 ,
wherein the filter medium has a dust holding capacity of at least 70 g/m 2 and at most 250 g/m 2 , and wherein the dust holding capacity is measured by taking a 100 cm 2 surface area of the filter medium and challenging the medium with a fine dust (0.1-80 μm) at a concentration of 200 mg/m 3 and a face velocity of 20 cm/s, and measuring the dust holding capacity when the pressure reaches 1800 Pa, and
wherein the filter medium has an initial dust capture efficiency of at least 90% for 10 micron particles.

24. The filter element of claim 1 ,
wherein the filter medium has a dust holding capacity of at least 70 g/m 2 and at most 250 g/m 2 , and wherein the dust holding capacity is measured by taking a 100 cm 2 surface area of the filter medium and challenging the medium with a fine dust (0.1-80 μm) at a concentration of 200 mg/m 3 and a face velocity of 20 cm/s, and measuring the dust holding capacity when the pressure reaches 1800 Pa, and
wherein the filter medium has an initial dust capture efficiency of at least 90% for 10 micron particles.

25. The filter element of claim 24 , wherein the filter element is an automotive air filter.

26. The filter element of claim 24 , wherein the second layer comprises a plurality of fibers having an average diameter of at least 0.2 microns and at most 1.0 micron.

27. The filter element of claim 1 , wherein the filter medium has an MD Gurley stiffness of from 4,000 mg to 5,000 mg.

28. The filter element of claim 1 , wherein the filter medium has an initial dust capture efficiency for 10 micron particles of at least 92%.

29. The filter element of claim 1 , wherein the second layer has a basis weight between 0.2 g/m 2 and 8 g/m 2 .

30. The method of claim 15 , wherein the second layer comprises meltblown fibers having an average diameter of at least 0.2 microns and at most 1.5 microns.

31. The filter element of claim 1 , wherein the third layer has a thickness of at least 5 microns and less than 100 microns.

32. The method of claim 15 , wherein the third layer has a thickness of at least 5 microns and less than 100 microns.

33. The filter element of claim 1 , wherein the second layer has a thickness of at least 5 microns and less than 0.001 inches.

34. The method of claim 15 , wherein the second layer has a thickness of at least 5 microns and less than 0.001 inches.

Assignees

• Wertz John A
• Healey David T
• Freeman William S
• Manns John L
• Rowlands Mark
• Hollingsworth & Vose Co

Inventors

• Wertz John A
• Healey David T
• Freeman William S
• Manns John L
• Rowlands Mark

Classifications

• Y10T442/60

  Nonwoven fabric [i.e., nonwoven strand or fiber material] · CPC title

• Y10T442/10

  Scrim [e.g., open net or mesh, gauze, loose or open weave or knit, etc.] · CPC title

• B01D2239/0681

  The layers being joined by gluing · CPC title

• B01D2239/0654

  Support layers · CPC title

• B01D2275/10

  Multiple layers · CPC title