Methods for Producing a Coated Abrasive Article for Polishing or Lapping Applications

Abstract

Methods are provided for forming an abrasive coating on a surface of a backing. An abrasive slurry includes a continuous phase, a first discontinuous phase of abrasive particles dispersed in the continuous liquid phase, and a second discontinuous phase of binder precursor particles dispersed in the continuous liquid phase, so that the continuous liquid phase carries the first and second discontinuous phases. A coated abrasive article is formed by coating the abrasive slurry onto the surface of the backing, and then removing the continuous phase.

Having thus described the invention, what is claimed is: 
     
         1 . A method of manufacturing a coated abrasive article comprising:
 (a) providing a flexible backing having a surface configured for being coated with an abrasive coating;   (b) providing an abrasive slurry including a continuous liquid phase, which comprises at least 50% per weight of water, and at least 0.001% per weight of fluorosurfactant;   a first discontinuous phase including abrasive particles dispersed in the continuous liquid phase; and   a second discontinuous phase including a waterborne binder precursor particle dispersion in the continuous liquid phase,   wherein the continuous liquid phase carries the first and second discontinuous phases,   wherein the volume ratio of abrasive particles to binder precursor particles is 0.05 to 3, and wherein the first and the second discontinuous phases comprise between 5% and 60% of the abrasive slurry by volume;   (c) coating the abrasive slurry onto the surface of the flexible backing;   (d) removing at least 50% per weight of the continuous liquid phase by evaporation; and   (e) coalescing the binder precursor particles at the surface of the flexible backing to form a coating with solid continuous binder phase disposed about the abrasive particles.   
     
     
         2 . A method of manufacturing a coated abrasive article comprising:
 (a) providing a flexible backing having a surface configured for being coated with an abrasive coating;   (b) providing an abrasive slurry including   
       a continuous liquid phase, which comprises at least 60% per weight of water, and at least 0.001% per weight of fluorosurfactant;
 a first discontinuous phase including abrasive particles dispersed in the continuous liquid phase; and 
 a second discontinuous phase including a waterborne binder precursor particle dispersion in the continuous liquid phase, 
 wherein the continuous liquid phase carries the first and second discontinuous phases, wherein the volume ratio of abrasive particles to binder precursor particles is 0.05 to 3, wherein the first and the second discontinuous phases comprise between 5% and 60% of the abrasive slurry by volume, and wherein the viscosity of the abrasive slurry is less than 100,000 cP; 
 (c) coating the abrasive slurry onto the surface of the flexible backing; 
 (d) removing at least 60% per weight of the continuous liquid phase by evaporation; and 
 (e) coalescing the binder precursor particles at the surface of the flexible backing. 
 
     
     
         3 . The method of  claim 2 , wherein the continuous liquid phase comprises at least about 90% per weight of water and wherein the abrasive and binder precursor particles comprise between 5% and 50% of the slurry by volume and the method comprises removing at least 90% per weight of the continuous liquid phase by evaporation. 
     
     
         4 . The method of  claim 2 , wherein the coalesced binder precursor particles form a continuous phase around the abrasive particles. 
     
     
         5 . The method of  claim 4 , wherein the continuous liquid phase comprises at least one coalescing agent configured to reduce the film forming temperature of the binder precursor particle dispersion. 
     
     
         6 . The method of  claim 5 , wherein the waterborne binder precursor particle dispersion is selected from the group consisting of waterborne acrylics emulsion, waterborne polyurethanes dispersion, waterborne urethane-acrylic copolymers dispersion, waterborne polyesters dispersion, waterborne alkyds dispersion, waterborne epoxies dispersion, waterborne phenoxy dispersion, waterborne melamine dispersion, waterborne polyamide dispersion, waterborne polyimide dispersion, waterborne cyanate esters dispersion, and combinations thereof. 
     
     
         7 . The method of  claim 2  wherein the second discontinuous phase comprises a cross-linkable resin, the method comprising thermally curing the abrasive slurry coating using at least one energy source. 
     
     
         8 . The method of  claim 7 , comprising transmitting energy from the energy source by convection, conduction, radiation, or combinations thereof. 
     
     
         9 . The method of  claim 7 , the continuous liquid phase comprises a curing agent selected from the group consisting of metal ion crosslinkers, polyaldehydes, polyaziridines, polyisocyanates, polysulfides, imidazoles, dicyandiamines, polyamidoamines, polyamides, polyamines, functionalized silanes, functionalized siloxane, carbodiimides, peroxides, and combinations thereof. 
     
     
         10 . The method of  claim 2 , wherein the second discontinuous phase comprises binder precursor particles of:
 at least about 5 nanometers in size; and   up to about 50 micrometers in size.   
     
     
         11 . The method of  claim 10 , wherein the second discontinuous phase comprises binder precursor particles of:
 at least about 10 nanometers in size; and   up to about 10 micrometers in size.   
     
     
         12 . The method of  claim 11 , wherein the second discontinuous phase comprises binder precursor particles of:
 at least about 50 nanometers in size; and   up to about 2 micrometers in size.   
     
     
         13 . The method of  claim 2 , wherein the abrasive particles are selected from the group consisting of natural diamond, synthetic diamond, cubic boron nitride, aluminum oxide, heat treated aluminum oxide, white fused aluminum oxide, black silicon carbide, green silicon carbide, titanium diboride, boron carbide, tungsten carbide, titanium carbide, garnet, fused alumina zirconia, sol gel abrasive material, silica, silicate, iron oxide, zirconium oxide, titanium dioxide, tin oxide, cerium oxide, rare earth containing ceramic materials, aluminum oxide containing ceramic material, zirconium oxide, chromium oxide, and mixtures thereof. 
     
     
         14 . The method of  claim 2 , wherein the abrasive slurry comprises at least one adhesion promoter selected from the group consisting of silanes, titanates, zirconates, phosphates, phosphonates, phosphinates, and combinations thereof. 
     
     
         15 . The method of  claim 2 , wherein the abrasive slurry further comprises a foam control agent. 
     
     
         16 . The method of  claim 2 , wherein the abrasive slurry further comprises a wetting agent. 
     
     
         17 . The method of  claim 2 , wherein the abrasive slurry comprises a rheology modifier and the weight ratio of the rheology modifier to the quantity of water in the slurry is between 0.0005 and 0.10 whereby the viscosity of the abrasive slurry is adjusted to a value between 10 cP and 50,000 cP. 
     
     
         18 . The method of  claim 2 , wherein the flexible backing is selected from the group consisting of plastic film, metallic foil, cloth, paper, foam and combinations thereof. 
     
     
         19 . A method of manufacturing a coated abrasive article comprising:
 (a) providing a flexible backing having a surface configured for being coated with an abrasive coating,   
       wherein the flexible backing is selected from the group consisting of plastic film, metallic foil, cloth, paper, foam and combinations thereof;
 (b) providing an abrasive slurry including a continuous liquid phase, which comprises at least 90% per weight of water, and at least 0.01% per weight of fluorosurfactant; 
 a first discontinuous phase including abrasive particles dispersed in the continuous liquid phase; and 
 a second discontinuous phase including a waterborne binder precursor particle dispersion in the continuous liquid phase, 
 wherein the continuous liquid phase carries the first and second discontinuous phases, wherein the volume ratio of abrasive particles to binder precursor particles is 0.05 to 2, and wherein the first and the second discontinuous phases comprise between 10% and 40% of the abrasive slurry by volume; 
 wherein the waterborne binder precursor particle dispersion is selected from the group consisting of waterborne acrylics emulsion, waterborne polyurethanes dispersion, waterborne urethane-acrylic copolymers dispersion, waterborne polyesters dispersion, waterborne alkyds dispersion, waterborne epoxies dispersion, waterborne phenoxy dispersion, waterborne melamine dispersion, waterborne polyamide dispersion, waterborne polyimide dispersion, waterborne cyanate esters dispersion, and combinations thereof; 
 
       wherein the continuous liquid phase comprises a curing agent selected from the group consisting of metal ion crosslinkers, polyaldehydes, polyaziridines, polyisocyanates, polysulfides, imidazoles, dicyandiamines, polyamidoamines, polyamides, polyamines, functionalized silanes, functionalized siloxane, carbodiimides, peroxides, and combinations thereof.
 (c) coating the abrasive slurry onto the surface of the flexible backing; 
 (d) removing at least 90% per weight of the continuous liquid phase by evaporation; 
 (e) coalescing the binder precursor particles at the surface of the flexible backing to form a coating with solid continuous binder phase disposed about the abrasive particles; and 
 (f) thermally curing the coating using at least one energy source. 
 
     
     
         20 . The method of  claim 19 , wherein the continuous liquid phase comprises at least 0.02% per weight of fluorosurfactant.