Finishing Mediums And Finishing Suspensions

Abstract

Described are finishing mediums for removing support material and/or for surface finishing of objects made via additive manufacturing techniques. The finishing medium is an aqueous solution containing 1-20% by weight a polyol, 1-20% by weight an anti-corrosion agent, 0.001-10% by weight a hydrotrope. The finishing medium may optionally suspend media particles, thereby forming a finishing suspension. Also described are methods of using the finishing media and finishing suspensions described herein.

1 . A finishing medium comprising:
 1-20% by weight a polyol;   optionally, 1-20% by weight an anti-corrosion agent;   0.001-10% by weight a hydrotrope; and   water.   
     
     
         2 . The finishing medium of  claim 1 , comprising:
 1-20% by weight a polyol;   1-20% by weight an anti-corrosion agent;   0.001-10% by weight a hydrotrope; and   the remainder is water.   
     
     
         3 . The finishing medium of  claim 1 , wherein the polyol is chosen from ethylene glycol, propylene glycol, glycerol, methoxytriglycol, ethoxytriglycol, butoxytriglycol, diethylene glycol n-butyl 30 ether acetate, diethylene glycol monobutyl ether, ethylene glycol n-butyl ether acetate, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, ethylene glycol phenyl ether, diethylene glycol monohexyl ether, ethylene glycol monohexyl ether, diethylene glycol monomethyl ether, ethylene glycol monopropyl ether, di(propylene glycol) methyl ether, dipropylene glycol methyl ether acetate, dipropylene glycol n-butyl ether, propylene glycol diacetate, propylene glycol methyl ether, propylene glycol monomethyl ether acetate, propylene glycol n-butyl ether, propylene glycol phenyl ether, tripropylene glycol methyl ether, tripropylene glycol n-butyl ether, dipropylene glycol dimethyl ether, 2-butoxyethanol, and combinations thereof. 
     
     
         4 . The finishing medium of  claim 1 , wherein the anti-corrosion agent is chosen from one or more organooxygen compound, one or more organoamine compound, one or more organosulfur compound, one or more organophosphorus compound, and combinations thereof. 
     
     
         5 . The finishing medium of  claim 1 , wherein the anti-corrosion agent is chosen from ethanolamine, diethanolamine, zinc dialkyldithiophosphate, benzotriazole, dibutylamine, and combinations thereof. 
     
     
         6 . The finishing medium of  claim 1 , wherein the hydrotrope is chosen from sodium xylene sulfonate, xylene sulfonic acid, calcium xylene sulfonate, potassium xylene sulfonate, cumene sulfonic acid, sodium cumene sulfonate, toluene sulfonic acid, sodium toluene sulfonate, and combinations thereof. 
     
     
         7 . The finishing medium of  claim 6 , wherein the hydrotrope is a mixture of hydrotrope isomers. 
     
     
         8 . The finishing medium of  claim 6 , wherein the hydrotrope is provided via an aqueous solution comprising 1-50% by weight a hydrotrope. 
     
     
         9 . The finishing medium of  claim 1 , wherein the finishing medium has a pH of 4 to 14. 
     
     
         10 . The finishing medium of  claim 1 , wherein:
 the polyol is propylene glycol;   the anti-corrosion agent is triethanolamine; and   the hydrotrope is an aqueous solution comprising 40% by weight sodium xylene sulfonate.   
     
     
         11 . The finishing medium of  claim 1 , comprising:
 10% by weight propylene glycol;   10% by weight triethanolamine;   4% by weight the aqueous solution having 40% by weight sodium xylene sulfonate; and   76% by weight water,   wherein the finishing medium has pH of 4 to 14.   
     
     
         12 . A finishing suspension comprising a finishing medium of  claim 1  and media particles. 
     
     
         13 . The finishing suspension of  claim 12 , wherein the media particles are chosen from aluminum-based particles, stainless steel particles, steel particles, ceramic particles, and combinations thereof. 
     
     
         14 . The finishing suspension of  claim 12 , wherein the media particles are chosen from glass beads, aluminum oxide, silica, zirconium oxide, zirconia, zirconium, silicon carbide, plastic, garnet, copper, corn cob, walnut shells, mica, feldspar, pumice, and combinations thereof. 
     
     
         15 . The finishing suspension of  claim 12 , wherein the media particles have a longest linear dimension of 1-1000 μm. 
     
     
         16 . A method of finishing an object made from an additive manufacturing technique (“AMT Object”) comprising, applying a finishing suspension of  claim 12  to an AMT Object such that a portion of the AMT Object and/or support material or a portion thereof is removed. 
     
     
         17 . The method of  claim 16 , wherein applying the finishing suspension comprises spraying the finishing suspension at the AMT Object. 
     
     
         18 . The method of  claim 17 , wherein the finishing suspension is sprayed at a pressure of 0-60 psi. 
     
     
         19 . The method of  claim 16 , wherein the finishing suspension is at a temperature of 50-140° F. 
     
     
         20 . The method of  claim 16 , wherein the AMT Object is made by fused deposition modeling, selective laser sintering, stereolithography, multi-jet fusion, direct metal laser sinter/binder jetting methods, or a combination thereof.