Filter media and elements
Fibrous filter medium that includes a melt-blown filter layer comprising melt-blown fibers and a high-efficiency glass-containing filter layer comprising glass fibers.
1. An air filter medium comprising:
a melt-blown filter layer comprising melt-blown fibers; and
a high-efficiency glass-containing filter layer comprising glass fibers and multi-component binder fibers; and
an optional support layer;
wherein the layers are configured and arranged for placement in an air stream;
further wherein the glass-containing layer comprises a hydrophobic coating, wherein the glass-containing layer is coated with the hydrophobic coating.
2. The filter medium of claim 1 , wherein the hydrophobic coating comprises a fluorochemical.
3. The filter medium of claim 1 , wherein the melt-blown filter layer is the most upstream layer.
4. The filter medium of claim 1 , wherein the glass-containing filter layer is positioned between the melt-blown filter layer and the support layer.
5. The filter medium of claim 1 , wherein the multi-component binder fibers of the glass-containing filter layer comprise bicomponent fibers having a low melting point polyester sheath and a higher melting point polyester core.
6. The filter medium of claim 1 , wherein the melt-blown filter layer is electrostatically charged.
7. The filter medium of claim 1 comprising a support layer, wherein the support layer is a spunbond layer.
8. The filter medium of claim 1 , wherein the filter medium displays a hydrostatic head of at least 10 inches (25.4 cm) of water.
9. The filter medium of claim 1 , wherein two or more layers are laminated together.
10. An air filter medium comprising:
a melt-blown filter layer comprising melt-blown fibers having an average diameter of greater than 1.5 microns; and
a high-efficiency glass-containing filter layer comprising glass fibers having an average diameter of less than 2 microns and multi-component binder fibers; and
a support layer;
wherein the melt-blown filter layer is the most upstream layer and the glass-containing layer is positioned between the melt-blown layer and the support layer.
11. The filter medium of claim 10 , wherein the glass-containing layer comprises a hydrophobic coating, wherein the glass-containing layer is coated with the hydrophobic coating.
12. The filter medium of claim 11 , wherein the hydrophobic coating comprises a fluorochemical.
13. The filter medium of claim 10 , wherein two or more layers are laminated together.
14. The air filter medium of claim 10 , wherein the multi-component binder fibers of the glass-containing filter layer comprise bicomponent fibers having a low melting point polyester sheath and a higher melting point polyester core.
15. The filter medium of claim 10 , wherein the melt-blown filter layer is electrostatically charged.
16. The filter medium of claim 10 , wherein the support layer is a spunbond layer.