Methods for Substrate Coating and Use of Additive-Containing Powdered Coating Materials in Such Methods

Abstract

The present invention relates to the use of a particle-containing powdered coating material, wherein an additive has been at least partially applied to the surface of the particles, in coating methods, in particular in cold gas spraying, flame spraying, high-speed flame spraying, thermal plasma spraying and non-thermal plasma spraying. Furthermore, the present invention relates to coating methods, in particular the above-named methods, using the powdered coating material according to the invention.

1 . A process for producing a coating, comprising:
 introducing a particle-containing powdered coating material into a coating method selected from the group consisting of cold gas spraying, flame spraying, high-speed flame spraying, thermal plasma spraying and non-thermal plasma spraying, wherein the particles of the powdered coating material comprise at least one additive.   
     
     
         2 . The process according to  claim 1 , wherein the weight proportion of the at least one additive is at most 32 wt.-%, relative to the total weight of the coating material and the additive. 
     
     
         3 . The process according to  claim 1 , wherein the carbon content of the powdered coating material comprising the at least one additive is from 0.01 wt.-% to 15 wt.-%, relative to the total weight of the coating material and the additive. 
     
     
         4 . The process according to  claim 1 , wherein the weight proportion of the at least one additive is at least 0.02 wt.-%, relative to the total weight of the coating material and the at least one additive. 
     
     
         5 . The process according to  claim 1 , wherein the at least one additive has at least 6 carbon atoms. 
     
     
         6 . The process according to  claim 1 , wherein the particles comprise metal particles, and the metal is selected from the group consisting of silver, gold, platinum, palladium, vanadium, chromium, manganese, cobalt, germanium, antimony, aluminum, zinc, tin, iron, copper, nickel, titanium, silicon, alloys and mixtures thereof. 
     
     
         7 . The process according to  claim 1 , wherein the coating method is selected from the group consisting of flame spraying and non-thermal plasma spraying. 
     
     
         8 . The process according to  claim 1 , wherein the at least one additive is free of stearic acid and/or oleic acid. 
     
     
         9 . The process according to  claim 1 , wherein the at least one additive is selected from the group consisting of polymers, monomers, silanes, waxes, oxidized waxes, carboxylic acids, phosphonic acids, derivatives and mixtures thereof. 
     
     
         10 . The process according to  claim 1 , wherein the at least one additive can be removed from the coated particles using organic and/or aqueous solvent. 
     
     
         11 . The process according to  claim 1 , wherein the powdered coating material has a particle-size distribution with a D 50  value ranging from 1.5 to 53 μm. 
     
     
         12 . A method for coating a substrate selected from the group consisting of cold gas spraying, flame spraying, high-speed flame spraying, thermal plasma spraying and non-thermal plasma spraying,
 the method comprising:   (a) introducing a particle-containing powdered coating material into a medium directed onto a substrate to be coated by cold gas spraying, flame spraying, high-speed flame spraying, thermal plasma spraying or non-thermal plasma spraying, wherein the particles comprise least one additive; and   (b) depositing the powdered coating material onto the substrate.   
     
     
         13 . The method according to  claim 12 , wherein the coating method is selected from the group consisting of flame spraying and non-thermal plasma spraying. 
     
     
         14 . The method according to  claim 12 , wherein the powdered coating material is conveyed as an aerosol. 
     
     
         15 . The method according to  claim 12 , wherein the medium directed onto the substrate is air or has been produced from air. 
     
     
         16 . The process according to  claim 1 , wherein the coating method is non-thermal plasma spraying. 
     
     
         17 . The method according to  claim 12 , wherein the coating method is non-thermal plasma spraying. 
     
     
         18 . The process of  claim 9 , wherein the waxes comprise natural waxes and synthetic waxes. 
     
     
         19 . The process of  claim 1 , wherein the powdered coating material has a span value according to formula I 
       
         
           
             
               
                 
                   
                     Span 
                     = 
                     
                       
                         
                           D 
                           90 
                         
                         - 
                         
                           D 
                           10 
                         
                       
                       
                         D 
                         50 
                       
                     
                   
                 
                 
                   
                     ( 
                     I 
                     ) 
                   
                 
               
             
           
         
         in the range of from 0.4 to 2.9. 
       
     
     
         20 . The process of  claim 1 , wherein at most 70% of the surface of the particles of the powdered coating material is covered with the additive. 
     
     
         21 . A coating produced according to the process of  claim 1 . 
     
     
         22 . A coated substrate produced according to the method of  claim 12 .