Adhesion promoting surface treatment or surface cleaner for metal substrates

Abstract

A coating composition comprising a phenolic resin, an alkoxy silane, and an acid. The coating composition of the present invention promotes adhesion between a multiple layer coating composition and a substrate and between the respective layers of the multiple layer coating composition.

1 - 31 . (canceled).  
     
     
         32 . A substrate coated with a coating composition comprising: 
 a. a phenolic resin;    b. an alkoxysilane; and    c. an acid.    
     
     
         33 . The substrate of  claim 32  wherein the substrate comprises cold rolled steel, electrogalvanized steel, or aluminum.  
     
     
         34 . The substrate of  claim 32 , wherein the coating composition is applied to the substrate at a film thickness of no more than about 0.1 mils.  
     
     
         35 . A method for coating a substrate comprising the following steps: 
 a. applying to the substrate a coating composition comprising a phenolic resin, an alkoxysilane, and an acid;    b. optionally applying a primer coating over the coating composition applied in step (a); and    c. applying a topcoat over the coating composition applied in step (a) or the primer coating applied in optional step (b).    
     
     
         36 . The method of  claim 35  wherein the alkoxysilane comprises an epoxy functional silane.  
     
     
         37 . The method of  claim 35  wherein the acid is selected from the group consisting of tannic acid, phosphoric acid, citric acid, and gallic acid and mixtures thereof.  
     
     
         38 . The method of  claim 35  wherein the phenolic resin is prepared by condensing a phenolic material with an aldehyde.  
     
     
         39 . The method of  claim 35  wherein said phenolic resin is present in an amount ranging from 0.1 to 99.8 percent by weight based on the total weight of the coating composition.  
     
     
         40 . The method of  claim 35  wherein said alkoxysilane is present in an amount ranging from 0.1 to 99.8 percent by weight based on the total weight of the coating composition.  
     
     
         41 . The method of  claim 35  wherein said acid is present in an amount ranging from 0.1 to 99.8 percent by weight based on the total weight of the coating composition.  
     
     
         42 . The substrate of  claim 32 , wherein the alkoxy group of the alkoxysilane contains from 1 to 6 carbon atoms.  
     
     
         43 . The substrate of  claim 32 , wherein the alkoxysilane comprises an epoxy functional silane.  
     
     
         44 . The substrate of  claim 32 , wherein the acid is selected from the group consisting of tannic acid, phosphoric acid, citric acid, and gallic acid and mixtures thereof.  
     
     
         45 . The substrate of  claim 32 , wherein the phenolic resin has an aromaticity of from 15 to 80 percent.  
     
     
         46 . The substrate of  claim 32 , wherein the alkoxysilane is selected from the group consisting of acryloxyalkoxysilanes, vinyl alkoxysilanes, ethylenically unsaturated acyloxysilanes, mercapto functional silanes, and amino functional silanes.  
     
     
         47 . The method of  claim 35 , wherein the alkoxy group of the alkoxysilane contains from 1 to 6 carbon atoms.  
     
     
         48 . The method of  claim 35 , wherein the phenolic resin has an aromaticity of from 15 to 80 percent.  
     
     
         49 . The method of  claim 35 , wherein the alkoxysilane is selected from the group consisting of acryloxyalkoxysilanes, vinyl alkoxysilanes, ethylenically unsaturated acyloxysilanes, mercapto functional silanes, and amino functional silanes.  
     
     
         50 . The method of  claim 35 , wherein the substrate comprises cold rolled steel, electrogalvanized steel, or aluminum.  
     
     
         51 . The method of  claim 35 , wherein the coating composition applied in step (a) is applied at a thickness of no more than about 0.1 mils.