Flame retardant emi shields

Abstract

An electromagnetic interference shield generally includes a resilient core member and an electrically conductive layer. An adhesive bonds the electrically conductive layer to the resilient core member. The adhesive can include halogen-free flame retardant.

What is claimed is: 
     
         1 . An electromagnetic interference (EMI) shield comprising:
 at least one resilient core member that is free of flame retardant;   at least one electrically conductive layer; and   at least one adhesive bonding the electrically conductive layer to the resilient core member, the adhesive including at least one halogen-free flame retardant;   wherein the adhesive is halogen-free; and   wherein the shield has a flame rating of V0 under Underwriter's Laboratories (UL) Standard No. 94.   
     
     
         2 . The shield of  claim 1 , wherein the adhesive includes not more than 70 percent by dry weight of halogen-free flame retardant. 
     
     
         3 . The shield of  claim 1 , wherein the adhesive includes 25 percent or more by dry weight of halogen-free flame retardant. 
     
     
         4 . The shield of  claim 1 , wherein the resilient core member comprises at least one foam material that is free of flame retardant. 
     
     
         5 . The shield of  claim 4 , wherein the foam material comprises at least one urethane foam material that is free of flame retardant. 
     
     
         6 . The shield of  claim 1 , wherein the adhesive bonds the electrically conductive layer to the resilient core member with a bond strength of at least four ounces per inch width. 
     
     
         7 . The shield of  claim 1 , wherein the adhesive bonds the electrically conductive layer to the resilient core member with a bond strength of at least ten ounces per inch width. 
     
     
         8 . The shield of  claim 1 , wherein:
 the adhesive includes not more than 70 percent by dry weight of halogen-free flame retardant;   the resilient core member comprises at least one foam material that is free of flame retardant; and   the adhesive bonds the electrically conductive layer to the resilient core member with a bond strength of at least four ounces per inch width.   
     
     
         9 . The shield of  claim 1 , wherein:
 the adhesive includes 25 percent or more by dry weight of halogen-free flame retardant;   the resilient core member comprises at least one foam material that is free of flame retardant; and   the adhesive bonds the electrically conductive layer to the resilient core member with a bond strength of at least four ounces per inch width.   
     
     
         10 . The shield of  claim 1 , wherein:
 the adhesive includes 25 percent or more by dry weight of halogen-free flame retardant; and/or   the resilient core member comprises at least one urethane foam material that is free of flame retardant; and/or   the adhesive bonds the electrically conductive layer to the resilient core member with a bond strength of at least ten ounces per inch width; and/or   the electrically conductive layer comprises at least one fabric material.   
     
     
         11 . The shield of  claim 1 , wherein:
 the adhesive includes not more than 70 percent by dry weight of halogen-free flame retardant; and/or   the resilient core member comprises at least one urethane foam material that is free of flame retardant; and/or   the adhesive bonds the electrically conductive layer to the resilient core member with a bond strength of at least ten ounces per inch width; and/or   the electrically conductive layer comprises at least one fabric material.   
     
     
         12 . The shield of  claim 1 , wherein the adhesive includes at least one halogen-free phosphorous-based flame retardant. 
     
     
         13 . The shield of  claim 1 , wherein the shield has only three layers, consisting of:
 a first layer that includes the resilient core member;   a second layer that includes the adhesive having the halogen-free flame retardant; and   a third layer that includes the electrically conductive layer.   
     
     
         14 . The shield of  claim 1 , further comprising halogen-free flame retardant and/or a halogen-free corrosion inhibitor provided to the electrically conductive layer. 
     
     
         15 . The shield of  claim 1 , wherein:
 the electrically conductive layer is free of flame retardant; and   the shield has a flame rating of V0 under Underwriter's Laboratories (UL) Standard No. 94 even with the electrically conductive layer and resilient core member being free of flame retardant.   
     
     
         16 . The shield of  claim 1 , wherein:
 the resilient core member comprises polyurethane foam;   the adhesive comprises at least one halogen-free phosphorus-based flame retardant, and a polyester adhesive layer which includes the halogen-free phosphorus-based flame retardant; and   the electrically conductive layer comprises a metalized fabric laminated to the polyester adhesive layer.   
     
     
         17 . The shield of  claim 1 , wherein the shield is entirely or substantially free of halogen. 
     
     
         18 . The shield of  claim 1 , wherein the adhesive comprises a solvent based adhesive. 
     
     
         19 . The shield of  claim 1 , wherein the adhesive comprises a solvent based polyester adhesive. 
     
     
         20 . The shield of  claim 1 , wherein the shield is halogen-free. 
     
     
         21 . The shield of  claim 20 , wherein:
 the adhesive includes 25 percent or more by dry weight of halogen-free flame retardant;   the resilient core member comprises at least one foam material that is free of flame retardant; and   the adhesive comprises a solvent based adhesive.   
     
     
         22 . The shield of  claim 1 , wherein:
 the adhesive includes not more than 75 percent by dry weight of halogen-free flame retardant;   the resilient core member comprises at least one foam material that is free of flame retardant; and   the adhesive comprises a solvent based adhesive.   
     
     
         23 . An electromagnetic interference (EMI) shield comprising:
 a resilient core member that is free of flame retardant;   an electrically conductive layer; and   a halogen-free adhesive disposed between the electrically conductive layer and the resilient core member, the halogen-free adhesive including a halogen-free flame retardant;   wherein the shield has a flame rating of V0 under Underwriter's Laboratories (UL) Standard No. 94.   
     
     
         24 . The shield of  claim 23 , wherein the adhesive bonds the electrically conductive layer directly to the resilient core member. 
     
     
         25 . A fabric-over-foam electromagnetic interference (EMI) shielding gasket comprising:
 at least one foam material;   at least one electrically conductive fabric; and   at least one halogen-free adhesive bonding the electrically conductive fabric to the foam material, the halogen-free adhesive including at least one halogen-free flame retardant;   wherein the gasket has a flame rating of V0 under Underwriter's Laboratories (UL) Standard No. 94; and   wherein the gasket is halogen-free.   
     
     
         26 . The gasket of  claim 25 , wherein:
 the adhesive comprises a solvent based adhesive that includes 25 percent or more by dry weight of halogen-free flame retardant; or   the adhesive comprises a solvent based adhesive that includes not more than 75 percent by dry weight of halogen-free flame retardant.