Multilayer films having flame retardant layers

Abstract

The present invention provides unified multilayer films having at least one layer that includes a flame retardant film layer. In preferred embodiments the flame retardant film layer is an internal layer. In particularly preferred embodiments of the present invention, multilayer films include flame retardant layers alternating with non flame retardant layers. In other preferred embodiments, multilayer films include alternating layers of different flame retardant materials.

What is claimed is:  
     
         1 . A unified multilayer film of at least five continuous film layers wherein at least one layer comprises a flame retardant film layer and at least one layer comprises a non-flame retardant film layer, wherein the flame retardant film comprises organic phosphorus flame retardants, inorganic flame retardants incorporated into a melt processible polymer.  
     
     
         2 . The multilayer film of    claim 1    wherein at least one internal layer comprises a flame retardant film layer.  
     
     
         3 . The multilayer film of    claim 1    that comprises flame-retardant film layers alternating with non flame retardant film layers.  
     
     
         4 . The multilayer film of    claim 3    wherein the flame retardant of the flame retardant films layers comprises the same flame retardant.  
     
     
         5 . The multilayer film of    claim 3    wherein the flame retardant of the flame retardant films layers comprises different flame retardants.  
     
     
         6 . The multilayer film of    claim 1    wherein the flame retardant additive comprises a mixture of two or more different flame retardant additives.  
     
     
         7 . The multilayer film of    claim 1    wherein the two outermost layers comprise a non flame retardant film.  
     
     
         8 . The multilayer film of    claim 1    which is oriented.  
     
     
         9 . The multilayer film of    claim 1    comprising a flame retardant film layer, a non flame retardant film layer, and a tie layer therebetween.  
     
     
         10 . The multilayer film of    claim 1    comprising at least ten layers.  
     
     
         11 . The multilayer film of    claim 1    further comprising at least one pressure sensitive adhesive layer on at least one surface.  
     
     
         12 . The multilayer film of    claim 1    wherein the flame retardant additive comprises from 10 to 90 weight percent of the unified multilayer film.  
     
     
         13 . The multilayer film of    claim 1    wherein the flame retardant additive comprises 40 wt. % or more in each flame retardant layer.  
     
     
         14 . The multilayer article of    claim 1   , wherein said melt processible polymer is a thermoplastic, a thermoplastic elastomeric or elastomeric material.  
     
     
         15 . The multilayer article of    claim 1   , wherein said melt processible polymer is selected from the group consisting of homo- and copolymers of ethylene, propylene and butylenes.  
     
     
         16 . The multilayer article of    claim 14   , wherein said a thermoplastic elastomeric material is selected from the group consisting of styrene-isoprene block copolymers, styrene-(ethylene-butylene) block copolymers, styrene-(ethylene-propylene) block copolymers, styrene-butadiene block copolymers; polyetheresters; elastomeric ethylene-propylene copolymers; thermoplastic elastomeric polyurethanes; polyvinylethers; and poly-α-olefins.  
     
     
         17 . The multilayer article of    claim 1    wherein the inorganic flame retardant additives are selected from the group consisting of antimony trioxide, antimony pentoxide, and sodium antimonate; barium metaborate, boric acid, sodium borate, zinc borate; aluminum tridhydroxide; magnesium hydroxide; molybdic oxide, ammonium molybdate, zinc molybdate, phosphoric acid; and zinc stannate.  
     
     
         18 . The multilayer article of    claim 1   , wherein said phosphorus flame retardant additive is selected from the group consisting of organic phosphonic acids, phosphonates, phosphinates, phosphonites, phosphinites, phosphine oxides, phosphines, phosphites or phosphates, phosphonitrilic chloride, phosphorus ester amides, phosphoric acid amides, phosphonic acid amides or phosphinic acid amides.  
     
     
         19 . The multilayer article of    claim 1   , wherein said phosophorus flame retardant additive is of the formula:  
       
         
           
           
               
               
           
         
         wherein each Q represents the same or different radicals selected from alkyl, cycloalkyl, aryl, alkyl substituted aryl, aryl substituted alkyl; halogen, hydrogen and combinations thereof provided that at least one of said Q's is aryl.  
       
     
     
         20 . The phosphorus additive of    claim 1    selected from the group consisting of phenylbisdodecyl phosphate, phenylbisneopentyl phosphate, phenylethylene hydrogen phosphate, phenyl-bis-3,5,5′-trimethylhexyl phosphate), ethyldiphenyl phosphate, 2-ethylhexyl di(p-tolyl) phosphate, diphenyl hydrogen phosphate, bis(2-ethyl-hexyl) p-tolylphosphate, tritolyl phosphate, bis(2-ethylhexyl)-phenyl phosphate, tri(nonylphenyl) phosphate, phenylmethyl hydrogen phosphate, di(dodecyl) p-tolyl phosphate, tricresyl phosphate, triphenyl phosphate, halogenated triphenyl phosphate, dibutylphenyl phosphate, 2-chloroethyldiphenyl phsophate, p-tolyl bis(2,5,5′-trimethylhexyl) phosphate, 2-ethylhexyldiphenyl phosphate, and diphenyl hydrogen phosphate.  
     
     
         21 . The multilayer article of    claim 1   , wherein said inherently flame retardant polymers incorporated into a melt processible polymer, comrprise particles of inherently flame retardant polymers dispersed in said melt processible polymer, or as a blend of inherently flame retardant polymers in said melt processible polymer.  
     
     
         22 . A process of preparing a multilayer film, the process comprising melt processing organic polymeric material to form a unified construction of at least 5 substantially contiguous film layers of organic polymeric material, wherein at least one layer is a flame retardant film layer and at least one layer is a non-flame retardant film layer and wherein the flame retardant film comprises organic phosphorus flame retardants, inorganic flame retardants.  
     
     
         23 . The process of    claim 22    wherein at least one flame retardant film layer is an internal layer  
     
     
         24 . The process of    claim 22    wherein all the layers are substantially simultaneously melt processed.