Wearable Abrasive Surfaces for Dry Applications

Abstract

Abrasive articles are disclosed that may be used in low speed dry sanding applications. The abrasive articles disclosed may be made entirely from abrasive materials or alternatively may be made by fastening abrasive surfaces to handles or tools. The abrasive articles of the present invention have abrasive surfaces with controlled wear rates that renew themselves during use. The self renewing abrasive surfaces of the present invention may be prepared by pressing a mixture of abrasive particles, hollow micro-particles and a minimal amount of binder together into a mold and subsequently allowing the binder to harden. The resulting abrasive articles are long lasting and may be made low in cost.

1 . An abrasive article for dry sanding application comprising: 
 at least one major abrasive surface;    a matrix material comprised of a binding agent; and    a plurality of hollow micro-particles and plurality of abrasive particles embedded throughout said matrix material, wherein said plurality of hollow micro-particles combined with said abrasive particles are present in sufficient quantity to promote a useable rate of wear at said major abrasive surface, whereby said major abrasive surface is continuously renewed during use.    
   
   
       2 . The abrasive article of  claim 1  wherein said plurality of hollow micro-particles is comprised of hollow micro-spheres.  
   
   
       3 . The abrasive article of  claim 1  wherein said binding agent is softer than said plurality of abrasive particles, whereby a usable rate of wear is achieved at said major abrasive surface.  
   
   
       4 . The abrasive article of  claim 1  wherein said major abrasive surface is discontinuous due to exposure of hollow micro-particles.  
   
   
       5 . The abrasive article of  claim 1  further comprised of a plurality of cavities at said major abrasive surface, whereby said major abrasive surface is discontinuous.  
   
   
       6 . The abrasive article of  claim 1  further comprising of a backing.  
   
   
       7 . The abrasive article of  claim 6 , wherein said matrix material with said embedded hollow micro-particles and said abrasive particles is attached to said backing in a discontinuous arrangement.  
   
   
       8 . The abrasive article of  claim 6  wherein said backing is flexible.  
   
   
       9 . The abrasive article of  claim 8  wherein said flexible backing is fabric.  
   
   
       10 . The abrasive article of  claim 1  wherein said plurality of abrasive particles comprise of material selected from the group consisting of aluminum oxide, silicon carbide, alumina zirconia, diamond, ceria, cubic boron nitride, garnet, ground glass, quartz, and combinations thereof.  
   
   
       11 . An abrasive composition having surface renewable properties for sanding applications comprising: 
 from about 5 percent to about 35 percent by weight of a polymeric binding agent;    from about 65 percent to about 95 percent by weight of abrasive particles; and    from about 25 percent to about 75 percent by volume of hollow micro-particles.    
   
   
       12 . The abrasive composition of  claim 11 , wherein said polymeric binding agent is a condensation polymer.  
   
   
       13 . The abrasive composition of  claim 12 , wherein said condensation polymer is selected from a group consisting of polyurethane, epoxy resins, and polyamides.  
   
   
       14 . The abrasive composition of  claim 12 , wherein said condensation polymer has a reduced molecular weight.  
   
   
       15 . The abrasive composition of  claim 11 , wherein said abrasive particles is selected from a group consisting of aluminum oxide, silicon carbide, alumina zirconia, diamond, ceria, cubic boron nitride, garnet, ground glass, quartz, and combinations thereof.  
   
   
       16 . The abrasive composition of  claim 11 , wherein said hollow micro-particles is comprised of hollow micro-spheres.  
   
   
       17 . The abrasive composition of  claim 11 , wherein said hollow micro-particles have a size ranging from about 50 microns to about 100 microns.