Footwear with bladder filter

Abstract

An article of athletic footwear having an air-filled bladder disposed in a sole structure is disclosed. The air-filled bladder is in fluid communication with ambient air through a filter that permits ambient air to enter the bladder but restricts liquids and particulates from entering the bladder. In operation, the filter and bladder may be portions of a bladder system that absorb shock when the footwear contacts a playing surface. Alternatively, the filter and bladder may be portions of a bladder system that ventilates the interior of the footwear. The filter may be formed of expanded polytetrafluoroethylene that is attached to a carrier.

That which is claimed is:  
     
         1 . An article of footwear for receiving a foot of a wearer, said article of footwear comprising: 
 an upper for covering at least a portion of the wearer's foot;    a sole structure attached to said upper;    an air-filled bladder in fluid communication with ambient air and attached to said article of footwear; and    a filter in fluid communication with said bladder and ambient air, said filter being structured to permit ambient air to enter said bladder and restrict liquids and particulates from entering said bladder.    
     
     
         2 . The article of footwear of  claim 1 , wherein said filter includes polytetrafluoroethylene.  
     
     
         3 . The article of footwear of  claim 2 , wherein said polytetrafluoroethylene is expanded polytetrafluoroethylene.  
     
     
         4 . The article of footwear of  claim 1 , wherein said filter includes one of the group consisting of high density polyethylene, ultrahigh molecular weight polyethylene, polyvinylidene fluoride, polypropylene, and ceramic filter materials.  
     
     
         5 . The article of footwear of  claim 1 , wherein said filter is hydrophobic and oleophobic.  
     
     
         6 . The article of footwear of  claim 1 , wherein a perforated layer is located over said filter, said perforated layer permitting air to access said filter.  
     
     
         7 . The article of footwear of  claim 6 , wherein said perforated layer prevents large particles and objects from contacting said filter.  
     
     
         8 . The article of footwear of  claim 1 , wherein said bladder is located in said sole structure.  
     
     
         9 . An article of footwear for receiving a foot of a wearer, said article of footwear comprising: 
 an upper for covering at least a portion of the wearer's foot;    a sole structure attached to said upper;    an air-filled bladder in fluid communication with ambient air and attached to said article of footwear; and    a polytetrafluoroethylene filter in fluid communication with said bladder and ambient air, said filter being structured to permit ambient air to enter said bladder and restrict liquids and particulates from entering said bladder.    
     
     
         10 . The article of footwear of  claim 9 , wherein said polytetrafluoroethylene is expanded polytetrafluoroethylene.  
     
     
         11 . The article of footwear of  claim 9 , wherein said filter is hydrophobic and oleophobic.  
     
     
         12 . The article of footwear of  claim 9 , wherein a perforated layer is located over said filter, said perforated layer permitting air to access said filter.  
     
     
         13 . The article of footwear of  claim 12 , wherein said perforated layer prevents large particles and objects from contacting said filter.  
     
     
         14 . The article of footwear of  claim 9 , wherein said bladder is located in said sole structure.  
     
     
         15 . The article of footwear of  claim 14 , wherein said filter is located in said sole structure.  
     
     
         16 . The article of footwear of  claim 14 , wherein said filter is located in said upper.