Artificial turf

Abstract

An artificial turf has a base layer and a multiplicity of blades fixed to and projecting upward from the base layer. Each of the blades is formed of an elongated plastic filament having a longitudinally extending inner part of plastic and a longitudinally extending outer part bonded to the inner part and of a plastic different from the inner-part plastic. Both parts extend the full length of the respective blade.

1 . An artificial turf comprising:
 a base layer; and   a multiplicity of blades fixed to and projecting upward from the base layer, each of the blades being formed of an elongated plastic filament having a longitudinally extending inner part of plastic and a longitudinally extending outer part bonded to the inner part and of a plastic different from the inner-part plastic, both parts extending generally a full length of the respective blade.   
   
   
       2 . The artificial turf defined in  claim 1  wherein the outer part is tubular and surrounds the inner part. 
   
   
       3 . The artificial turf defined in  claim 2  wherein the outer part is a polyolefin. 
   
   
       4 . The artificial turf defined in  claim 3  wherein the outer part is polyethylene. 
   
   
       5 . The artificial turf defined in  claim 4  wherein the outer part is linear low-density polyethylene. 
   
   
       6 . The artificial turf defined in  claim 2  wherein the inner part is polyamide or polyester. 
   
   
       7 . The artificial turf defined in  claim 6  wherein the inner part is Nylon 6, Nylon 6.6, Nylon 6.12, or Nylon 6.10. 
   
   
       8 . The artificial turf defined in  claim 2  wherein each part further comprises a tubular intermediate part surrounding the inner part, surrounded by the outer part, and of a plastic different from the plastics of at least one of the inner and outer parts. 
   
   
       9 . The artificial turf defined in  claim 8  wherein the inner part, the intermediate part, and the outer part all extend generally full lengths of the filament. 
   
   
       10 . The artificial turf defined in  claim 8  wherein the intermediate layer is formed of a polyamide/polyolefin copolymer or a polyolefin modified with maleic acid derivative. 
   
   
       12 . The artificial turf defined in  claim 8  wherein the outer part has a cross-sectional area equal to between 5% and 50% of a total cross-sectional area of the blade. 
   
   
       13 . The artificial turf defined in  claim 8  wherein the outer part has a cross-sectional area equal to between 10% and 40% of a total cross-sectional area of the blade. 
   
   
       14 . The artificial turf defined in  claim 8  wherein the intermediate part has a cross-sectional area equal to between 3% and 20% of a total cross-sectional area of the blade. 
   
   
       15 . The artificial turf defined in  claim 8  wherein the intermediate part has a cross-sectional area equal to between 5% and 15% of a total cross-sectional area of the blade. 
   
   
       16 . The artificial turf defined in  claim 8  wherein the outer part has a cross-sectional area equal to between 30% and 93% of a total cross-sectional area of the blade. 
   
   
       17 . The artificial turf defined in  claim 8  wherein the outer part has a cross-sectional area equal to between 35% and 80% of a total cross-sectional area of the blade. 
   
   
       18 . The artificial turf defined in  claim 1  wherein the inner part is formed with at least one longitudinally extending void.