Pavement markings comprising synthetic polymeric fibers

Abstract

The invention relates to thermoplastic pavement marking compositions comprising synthetic polymeric fibers.

What is claimed is:  
     
         1 . A pavement marking composition comprising synthetic polymeric fibers dispersed within a thermoplastic-based polymeric material, wherein the synthetic polymeric fibers have a melt point greater than the polymeric material.  
     
     
         2 . The pavement marking sheet of  claim 1  wherein the fibers are randomly dispersed within the polymeric material.  
     
     
         3 . The pavement marking composition of  claim 1  wherein the synthetic polymeric fibers have a melt point greater than 400° F.  
     
     
         4 . The pavement marking composition of  claim 1  wherein the synthetic polymeric fibers are selected from the group comprising polyester, polyamide, polypropylene, tetrafluoroethylene and copolymers thereof.  
     
     
         5 . The pavement marking composition of  claim 1  wherein said composition is provided as a sheet having a thickness ranging from about 0.25 mm to about 5 mm, said sheet having a downweb direction and crossweb direction.  
     
     
         6 . The pavement marking sheet of  claim 5  wherein the sheet is conformable.  
     
     
         8 . The pavement marking sheet of  claim 5  wherein the downweb direction and crossweb direction has a tear ratio that ranges from 0.5 to 2 when measured according to ASTM 1938.  
     
     
         9 . The pavement marking sheet of  claim 5  wherein the downweb direction and crossweb direction has a tear ratio that ranges from 0.7 to 1.3 when measured according to ASTM 1938.  
     
     
         10 . The pavement marking composition of  claim 1  wherein the synthetic polymeric fiber ranges from about 0.2 weight-% to about 2 weight-%.  
     
     
         11 . The pavement marking of  claim 1  wherein the polymeric material is selected from the group comprising alkyd thermoplastic and hydrocarbon thermoplastic.  
     
     
         12 . The pavement marking of  claim 11  wherein the polymeric material is a hydrocarbon thermoplastic.  
     
     
         13 . The pavement marking of  claim 12  wherein the polymeric material comprises an acid containing copolymer of ethylene.  
     
     
         14 . The pavement marking composition of  claim 1  wherein the composition comprises other ingredients selected from the group comprising reflective elements, extender resins, fillers, and pigments.  
     
     
         15 . The pavement marking of  claim 1  wherein the composition comprises magnetic particles.  
     
     
         16 . The pavement marking composition of  claim 1  wherein the synthetic polymeric fibers have a fiber length of at least 6 mm.  
     
     
         17 . The pavement marking composition of  claim 1  wherein the synthetic polymeric fibers have a fiber length of at least 10 mm.  
     
     
         18 . A method of making a pavement marking comprising: 
 providing a composition comprising a thermoplastic-based polymeric material and synthetic polymeric fibers;    heating the composition to a temperature wherein the composition is extrudeable and the synthetic polymeric fibers are unmelted; and    extruding the composition on a pavement surface.    
     
     
         19 . A method of making a pavement marking comprising: 
 dry blending a thermoplastic polymer and synthetic polymeric fibers;    melting and mixing the blend; and    extruding the blend onto a pavement surface at a temperature less than the melt point of the synthetic polymeric fibers.