ARTICLES COMPRISING BINDERS, CROSS-LINKING AGENTS AND/OR OTHER COMPONENTS, AND RELATED METHODS

1 . An article, comprising:

cotton fibers;

a cross-linking agent;

a binder resin; and

an additive.

2 - 19 . (canceled)

20 . A filter medium, comprising:

a first phase comprising a first plurality of fibers and a second plurality of fibers different from the first plurality of fibers;

a second phase comprising 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; and

a transition phase between the first and second phases, wherein the transition phase comprises at least a portion of the first plurality of fibers, at least a portion of the second plurality of fibers, at least a portion of the third plurality of fibers, and at least a portion of the fourth plurality of fibers, and wherein at least a portion of the first plurality of fibers, at least a portion of the second plurality of fibers, at least a portion of the third plurality of fibers, and at least a portion of the fourth plurality of fibers are intermingled with each other;

wherein the air permeability of the first plurality of fibers is higher than the air permeability of the second plurality of fibers, and the air permeability of the third plurality of fibers is higher than the air permeability of the fourth plurality of fibers;

wherein a weight ratio of the first plurality of fibers to the second plurality of fibers is from 50:50 to 97:3;

wherein the first and second phases form a wet laid structure;

wherein the first, second, third, and fourth pluralities of fibers are wet laid;

wherein the basis weight ratio of the first phase to the second phase is from 30:70 to 70:30;

wherein the filter medium has a dust holding capacity from 1 g to 3 g measured according to a Palas flat sheet test; and

wherein the filter medium has a mean flow pore size of at least 25 microns and at most 1000 microns.

21 . A filter medium, comprising:

a first phase comprising a first plurality of fibers and a second plurality of fibers different from the first plurality of fibers;

a second phase comprising 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; and

a transition phase between the first and second phases, wherein the transition phase comprises at least a portion of the first plurality of fibers, at least a portion of the second plurality of fibers, at least a portion of the third plurality of fibers, and at least a portion of the fourth plurality of fibers, and wherein at least a portion of the first plurality of fibers, at least a portion of the second plurality of fibers, at least a portion of the third plurality of fibers, and at least a portion of the fourth plurality of fibers are intermingled with each other;

wherein the air permeability of the first plurality of fibers is higher than the air permeability of the second plurality of fibers, and the air permeability of the third plurality of fibers is higher than the air permeability of the fourth plurality of fibers;

wherein a weight ratio of the first plurality of fibers to the second plurality of fibers is from 50:50 to 97:3;

wherein the first and second phases form a wet laid structure;

wherein the first, second, third, and fourth pluralities of fibers are wet laid;

wherein the basis weight ratio of the first phase to the second phase is from 30:70 to 70:30; and

wherein the filter medium has a dust holding capacity from 1 g to 3 g measured according to a Palas flat sheet test.

22 . The filter medium of claim 20 , wherein the air permeability of the second or fourth plurality of fibers is from 5 CFM to 50 CFM.

23 . The filter medium of claim 20 , wherein the air permeability of the second plurality of fibers is from 15 CFM to 25 CFM.

24 . The filter medium of claim 20 , wherein the air permeability of the first or third plurality of fibers is from 50 CFM to 350 CFM.

25 . The filter medium of claim 20 , wherein the air permeability of the first or third plurality of fibers is from 100 CFM to 200 CFM.

26 . The filter medium of claim 20 , wherein the filter medium comprises a binder.

27 . The filter medium of claim 26 , wherein the binder is at most 35% of the basis weight of the filter medium.

28 . The filter medium of claim 26 , wherein the binder is at most 25% of the basis weight of the filter medium.

29 . The filter medium of claim 27 , wherein the binder comprises a material selected from the group consisting of polyvinyl acetate, an epoxy, a polyester, a polyvinyl alcohol, and/or an acrylic.

30 . The filter medium of claim 20 , wherein each of the first, second, third, and fourth fibers are formed of an organic polymeric material.

31 . The filter medium of claim 20 , wherein the filter medium has an air permeability of 2 CFM to 200 CFM.

32 . The filter medium of claim 20 , wherein the weight ratio of first to second phase is from 40:60 to 60:40.

33 . The filter medium of claim 20 , wherein the first phase comprises a mixture of softwood fibers and hardwood fibers.

34 . The filter medium of claim 20 , wherein the first or third plurality of fibers have an average fiber length from 1.5 mm to 6 mm.

35 . The filter medium of claim 20 , wherein the second or fourth plurality of fibers have an average fiber length of from 0.5 mm to 2 mm.

36 . The filter medium of claim 20 , wherein at least two of the first, second, third and fourth pluralities of fibers are either hardwood or softwood fibers.

37 . The filter medium of claim 20 , wherein the filter medium includes a weight ratio of the first and second pluralities of fibers of from 50:50 to 90:10, and a weight ratio of the third and fourth pluralities of fibers of from 10:90 to 50:50.

38 . The filter medium of claim 20 , wherein the filter medium has a mean flow pore size of from 25 microns to 125 microns.