Dish-shaped abrasive particles with a recessed surface

Abstract

Abrasive particles comprising dish-shaped abrasive particles each having a sidewall; each of the shaped abrasive particles comprising alpha alumina and having a first face and a second face separated by a thickness, t; and wherein either the first face or the second face is recessed or concave.

1 . Abrasive particles comprising: dish-shaped abrasive particles each having a sidewall, each of the dish-shaped abrasive particles comprising alpha alumina and having a first face and a second face separated by a sidewall having a varying thickness, T; wherein the first face is recessed and a thickness ratio of Tc/Ti for the dish-shaped abrasive particles is between 1.25 to 5.00. 
     
     
         2 . The abrasive particles of  claim 1  wherein the second face is substantially planar. 
     
     
         3 . The abrasive particles of  claim 2  wherein the first face comprises a substantially planar center portion and a plurality of raised corners. 
     
     
         4 . The abrasive particles of  claim 2  wherein the first face is concave. 
     
     
         5 . The abrasive particles of  claim 1 ,  2 ,  3 , or  4  comprising a draft angle α between the second face and the sidewall, and wherein the draft angle α is between about 95 degrees to about 125 degrees. 
     
     
         6 . The abrasive particles of  claim 1 ,  2 ,  3 , or  4  comprising a draft angle α between the second face and the sidewall, and wherein the draft angle α is between about 95 degrees to about 105 degrees. 
     
     
         7 . The abrasive particles of  claim 1 ,  2 ,  3 , or  4  comprising a perimeter of the first face and a perimeter of the second face and wherein the perimeter comprises a triangular shape. 
     
     
         8 . The abrasive particles of  claim 7  wherein the triangular shape comprises an equilateral triangle. 
     
     
         9 . The abrasive particles of  claim 1  comprising a radius of a sphere curved fitted to the first face by image analysis and wherein the radius is between about 1 mm to about 25 mm. 
     
     
         10 . The abrasive particles of  claim 9  wherein the radius of the sphere curved fitted to the first face by image analysis is between about 1 mm to about 14 mm. 
     
     
         11 . Abrasive particles comprising: dish-shaped abrasive particles each having a sidewall, each of the dish-shaped abrasive particles comprising alpha alumina and having a first face and a second face separated by a thickness, T, and wherein the first face is convex and the second face is concave. 
     
     
         12 . The abrasive particles of  claim 11  comprising a radius of a sphere curved fitted to the second face by image analysis and wherein the radius is between about 1 mm to about 25 mm. 
     
     
         13 . The abrasive particles of  claim 11  or  12  comprising a volumetric aspect ratio and wherein the volumetric aspect ratio is greater than about 1.50. 
     
     
         14 . The abrasive particles of  claim 13  comprising a perimeter of the first face and a perimeter of the second face and wherein the perimeter comprises an equilateral triangular shape. 
     
     
         15 . Abrasive particles comprising: dish-shaped abrasive particles each having a sidewall, each of the dish-shaped abrasive particles comprising alpha alumina and having a first face and a second face separated by a sidewall having a varying thickness, T, and wherein the first face is recessed and the second face is recessed. 
     
     
         16 . The abrasive particles of  claim 15  wherein the first face is concave and the second face is concave. 
     
     
         17 . The abrasive particles of  claim 15  wherein the first face comprises a substantially planar center portion and a plurality of raised corners, and the second face comprises a substantially planar center portion and a plurality of raised corners. 
     
     
         18 . The abrasive particles of  claim 15 ,  16 , or  17  comprising a perimeter of the first face and a perimeter of the second face and wherein the perimeter comprises an equilateral triangular shape. 
     
     
         19 . The abrasive particles of  claim 1 ,  11  or  15  comprising a binder forming an abrasive article selected from the group consisting of bonded abrasive articles, coated abrasive articles, nonwoven abrasive articles, and abrasive brushes. 
     
     
         20 . The abrasive particles of  claim 1 ,  11 , or  15  comprising a make coat on a first major surface of a backing and a majority of the dish-shaped abrasive particles adhered to the make coat by the sidewall, the dish-shaped abrasive particles forming an abrasive layer, the abrasive layer coated with a size coat, and wherein the abrasive layer comprises at least 5 percent by weight of the dish-shaped abrasive particles. 
     
     
         24 . Abrasive particles comprising: dish-shaped abrasive particles each having a sidewall, each of the dish-shaped abrasive particles comprising alpha alumina and having a first face and a second face separated the sidewall; and wherein the first face is recessed and an acute angle λ is present between the sidewall and the first face. 
     
     
         25 . The abrasive particles of  claim 24  comprising a perimeter of the first face and a perimeter of the second face and wherein the perimeter comprises a triangular shape. 
     
     
         26 . The abrasive particles of  claim 25  comprising a saw tooth point at each corner. 
     
     
         27 . The abrasive particles of  claim 25  comprising a draft angle α between the second face and the sidewall and wherein the draft angle α is between about 95 degrees to about 130 degrees.