Discontinuous Abrasive Surfaces Having Controlled Wear Properties

Abstract

Discontinuous abrasive surfaces are disclosed that may be employed in wet and/or dry applications. The discontinuous abrasive surfaces of the present invention may consist of abrasive containing protrusions attached to rigid or flexible surfaces arranged in one or more layers, or alternatively may be comprised of closed cell foam compositions impregnated with abrasive materials such as aluminum oxide. The closed cell foam compositions of the present invention may soften with water to provide a cushioning layer for abrasive particles at the working surface. The voids present in the discontinuous abrasive surfaces of the present invention serve to hold water in wet applications and remove debris. The resulting discontinuous abrasive particle releasing surfaces are long lasting and may be made low in cost.

1 . An abrasive article for dry sanding application comprising: 
 a backing having a first major surface and a second major surface;    a plurality of abrasive particle releasing protrusions attached to said backing to at least one said major surface, said plurality of particle releasing protrusions are comprised of abrasive particles dispersed within a softer material matrix and said particle releasing protrusions are formed into a plurality of layers.    
   
   
       2 . The abrasive article for dry sanding application of  claim 1  wherein said protrusions are further comprised of hollow micro-particles.  
   
   
       3 . The abrasive article for dry sanding application of  claim 2  wherein said hollow micro-particles are hollow microspheres.  
   
   
       4 . The abrasive article for dry sanding application of  claim 1  wherein said backing is rigid.  
   
   
       5 . The abrasive article for dry sanding application of  claim 1  wherein said backing is flexible.  
   
   
       6 . The abrasive article of  claim 1  wherein said abrasive article is a nail file.  
   
   
       7 . An abrasive composition for sanding applications comprising: 
 a plurality of abrasive loaded granules, comprised of an abrasive particle embedded within a softer material matrix;    and a harder material matrix having a hardness greater than said softer material matrix wherein said plurality of abrasive loaded granules are embedded within said harder material matrix.    
   
   
       8 . The abrasive composition of  claim 7  wherein said abrasive loaded granules are comprised of a plurality of abrasive particles embedded within said softer material matrix.  
   
   
       9 . The abrasive composition of  claim 7  wherein said softer material matrix is hydrophilic.  
   
   
       10 . The abrasive composition of  claim 9  wherein said hydrophilic softer material matrix softens on exposure to water.  
   
   
       11 . The abrasive composition of  claim 9  wherein said hydrophilic softer material matrix expands on exposure to water.  
   
   
       12 . The abrasive composition of  claim 7  wherein said softer material matrix is a closed cell foam.  
   
   
       13 . The abrasive composition of  claim 7  wherein said softer material matrix is water soluble.  
   
   
       14 . The abrasive composition of  claim 13  further comprising a backing with at least one major surface, said major surface attached to a layer of said plurality of abrasive loaded granules embedded within said harder material matrix.  
   
   
       15 . The abrasive composition of  claim 13  further comprising a backing with at least one major surface, said major surface attached to a plurality of protrusions wherein said plurality of protrusions are comprised of said plurality of abrasive loaded granules embedded within said harder material matrix.  
   
   
       16 . The abrasive composition of  claim 15  wherein said plurality of protrusions are formed into a plurality of layers.  
   
   
       17 . The abrasive composition of  claim 7  further comprising a backing with at least one major surface, said major surface attached to a layer of said plurality of abrasive loaded granules embedded within said harder material matrix.  
   
   
       18 . The abrasive composition of  claim 7  further comprising a backing with at least one major surface, said major surface attached to a plurality of protrusions wherein said plurality of protrusions are comprised of said plurality of abrasive loaded granules embedded within said harder material matrix.  
   
   
       19 . The abrasive composition of  claim 18  wherein said plurality of protrusions are formed into a plurality of layers.  
   
   
       20 . An abrasive article for body sanding application comprising: 
 a rigid high-density polymeric closed cell foam substrate having at least one major surface, said at least one major surface having a discontinuous surface topography; and    a plurality of abrasive particles dispersed within said rigid polymeric closed cell foam, wherein said rigid polymeric closed cell foam is wearable at said major surface by said plurality of abrasive particles.    
   
   
       21 . The abrasive article of  claim 20  wherein said rigid high-density polymeric closed cell foam is a polyurethane foam having a density from about 8 pounds per cubic foot to about 20 pounds per cubic foot, whereby voids within said rigid high-density polymeric closed cell foam have a reduced size relative to a lower density foam.  
   
   
       22 . The abrasive article of  claim 21  wherein said polyurethane foam is formed with an excess of hydroxy functional polyol reactant whereby said major surface is facilitated in softening upon exposure to water and said major surface is free from unreacted isocyanate.  
   
   
       23 . The abrasive article of  claim 20  further comprising of a disinfectant.  
   
   
       24 . The abrasive article of  claim 20  further comprising of a scent.