Scratch resistant thermoplastic

Abstract

A process and resulting thermoplastic article ( 10 ) is provided suitable for use in constructing furniture. The thermoplastic article ( 10 ) contains hardened particulates ( 20 ) such as powders of alumina oxide or ceramic microspheres which bring about an improved cut and scratch resistance to the surface of the articles. The hardened particulates ( 20 ) may be integrally mixed with the extruded product or applied post-molding to a surface of the shaped article. In addition, spherical additives may be included in the extrusion polymer which reduces shear forces and provides an improved wood grain appearance in the extruded article.

That which is claimed is:  
     
         1 . A process of providing a wear resistant coating to a thermoplastic article comprising the steps of: 
 providing a thermoplastic article having a surface temperature heated to a softening temperature;    applying an effective amount of a particulate to a surface of the article, said particulate imparting wear resistant properties to the surface of the thermoplastic article,    mechanically pressing the particulate-containing surface with a pressure of about 150 to about 200 pounds per linear inch; and    allowing said thermoplastic article to cool.    
     
     
         2 . The process according to  claim 1  wherein said step of applying an effective amount of a particulate further comprises supplying said particulate at a concentration of about 1 to about 25 grams per square meter.  
     
     
         3 . The process according to  claim 1  wherein said particulate is selected from the group consisting of silicates, silica oxide, fumed silica, alumina, alumina oxides, ceramics, ceramic microspheres, and combinations thereof.  
     
     
         4 . The process according to  claim 1  wherein said particulate has an average particle diameter of between about 4 to about 10 microns.  
     
     
         5 . The process of forming a thermoplastic extruded sheet having a wear resistant surface comprising the steps of: 
 providing a thermoplastic sheet;    embossing a surface of said thermoplastic sheet, thereby imparting a matte finish to the sheet, the matte finish comprising a series of elevations and depressions;    warming the matte surface to a softening temperature;    applying a plurality of hardened particulates onto the matte surface; and    applying pressure to the matte surface and the particulates, thereby embedding the particulates into the matte surface.    
     
     
         6 . The process according to  claim 5  wherein said step of applying an effective amount of a particulate further comprises supplying said particulate at a concentration of about 1 to about 25 grams per square meter.  
     
     
         7 . The process according to  claim 5  wherein said particulate is selected from the group consisting of silicates, silica oxide, fumed silica, alumina, alumina oxides, ceramics, ceramic microspheres, and combinations thereof.  
     
     
         8 . The process according to  claim 5  wherein said particulates have an average particle diameter of between about 4 to about 10 microns.  
     
     
         9 . The process according to  claim 5  wherein said step of applying pressure further includes applying a pressure of between about 150 to about 200 pounds per linear inch.  
     
     
         10 . A process of providing a thermoplastic extrusion product comprising the steps of: 
 compounding a thermoplastic polymer selected from the group consisting of polyvinyl chloride, styrene-based polymers, olefins, and polyamides;    introducing into said thermoplastic resin in at least one of a compounding step or an extruding step an effective amount of a particulate;    extruding said thermoplastic polymer;    molding said thermoplastic polymer into a desired shape;    wherein said particulate additives increases wear resistance and cut resistance of the thermoplastic article.    
     
     
         11 . The process according to  claim 10  wherein said step of applying an effective amount of a particulate further comprises supplying said particulate at a concentration of about 1 to about 25 grams per square meter.  
     
     
         12 . The process according to  claim 10  wherein said particulate is selected from the group consisting of silicates, silica oxide, fumed silica, alumina, alumina oxides, ceramics, ceramic microspheres, and combinations thereof.  
     
     
         13 . The process according to  claim 10  wherein said particulates have an average particle diameter of between about 4 to about 10.  
     
     
         14 . A thermoplastic article comprising: 
 a molded thermoplastic panel, said panel having an upper surface and a lower surface;    a plurality of particulates selected from the group consisting of silicas, silica oxides, fumed silicas, alumina, alumina oxides, ceramics, ceramic microspheres, and combinations thereof, said plurality of particulates positioned within at least a portion of said panel which includes at least one of said upper surface or said lower surface;    wherein, said plurality of particulates improves the wear resistance of said at least one of said upper surface or said lower surface.    
     
     
         15 . The thermoplastic article according to  claim 14  wherein said plurality of particulates is concentrated along a surface region of at least one of said upper surface or said lower surface.  
     
     
         16 . The thermoplastic article according to  claim 14  wherein an upper surface of said panel is embossed, said embossed surface further engaging said plurality of particulates.  
     
     
         17 . The thermoplastic article according to  claim 15  wherein said plurality of particulates are present in a concentration of between about 1 to about 25 grams per square meter of said surface region.  
     
     
         18 . The thermoplastic article according to  claim 16  wherein said embossed surface further defines a concentration of said hardened particulates, said particles present in a concentration of between about 1 to about 25 grams per square meter.  
     
     
         19 . The thermoplastic article according to  claim 14  wherein said plurality of particulates is present in said thermoplastic panel in a concentration of between about 1% to about 10% by weight.  
     
     
         20 . A thermoplastic polymer for use in a die extrusion process comprising: 
 a polymer selected from the group consisting of polyvinyl chloride, styrene-based polymers, olefins, and polyamides and combinations thereof, the polymer having mixed therein an effective amount of a shear reducing spherical additive sufficient to reduce shear forces when the polymer is extruded through a die.    
     
     
         21 . The thermoplastic polymer according to  claim 20  wherein said spherical additive is present at a concentration of between about 1% to about 10% by weight.  
     
     
         22 . The thermoplastic polymer according to  claim 20  wherein said spherical additive is present in a concentration of at least about 4% to at least about 6% by weight.  
     
     
         23 . The thermoplastic polymer according to  claim 20  wherein said spherical additive is a solid ceramic microsphere.  
     
     
         24 . A thermoplastic article comprising: 
 an extruded thermoplastic panel having an upper surface and a lower surface, said panel further having a pigmented grain pattern defined therein;    about 1% to about 10% of a spherical additive, said spherical additive substantially uniformly distributed throughout said panel;    wherein said thermoplastic panel has a more uniform grain appearance across a width of said panel than a thermoplastic panel without the spherical additive.    
     
     
         25 . The thermoplastic article according to  claim 24  wherein said spherical additive is a solid ceramic microsphere.  
     
     
         26 . The thermoplastic article according to  claim 24  wherein said spherical additive is present in a concentration of at least about 4% to 6% by weight.