Cleaning composition for metal articles

Abstract

An aqueous cleaning composition includes at least one acid fluoride salt selected from ammonium bifluoride, sodium bifluoride, potassium bifluoride, calcium fluorophosphates, sodium fluorosilicates, and combinations of two or more thereof; at least one mineral acid adduct of urea; at least one surfactant; and at least one organic solvent. The cleaning composition is effective in removing deposited soil and corrosion products on a metal surface, particularly aluminum and aluminum alloy surfaces.

1 . An aqueous cleaning composition comprising:
 at least one acid fluoride salt selected from ammonium bifluoride, sodium bifluoride, potassium bifluoride, calcium fluorophosphates, sodium fluorosilicates, and combinations of two or more thereof;   at least one mineral acid adduct with urea;   at least one surfactant; and   at least one organic solvent.   
     
     
         2 . The aqueous cleaning composition of  claim 1  wherein the acid fluoride salt is ammonium bifluoride. 
     
     
         3 . The aqueous cleaning composition of  claim 1  wherein the mineral acid adduct with urea is selected from among the adducts of urea with perchloric acid; hydroiodic acid; hydrobromic acid; hydrochloric acid; sulfuric acid; nitric acid; phosphoric acid and combinations of two or more thereof. 
     
     
         4 . The aqueous cleaning composition of  claim 1  wherein the surfactant comprises a nonionic surfactant. 
     
     
         5 . The aqueous cleaning composition of  claim 4  wherein the nonionic surfactant comprises an ethoxylated alcohol. 
     
     
         6 . The aqueous cleaning composition  claim 1  wherein the surfactant comprises a cationic surfactant. 
     
     
         7 . The aqueous cleaning composition of  claim 6  wherein the cationic surfactant comprises dicocodimethyl ammonium chloride. 
     
     
         8 . The aqueous cleaning composition of  claim 1  wherein the surfactant comprises an amphoteric surfactant. 
     
     
         9 . The aqueous cleaning composition of  claim 8  wherein the amphoteric surfactant comprises cocoamidopropyl betaine. 
     
     
         10 . The aqueous cleaning composition of  claim 1  wherein the organic solvent comprises diethylene glycol monobutyl ether. 
     
     
         11 . The aqueous cleaning composition of  claim 1  wherein the composition is diluted with water in a ratio of cleaning composition:water of 1:1 to 1:10. 
     
     
         12 . An aqueous cleaning composition comprising:
 from about 1% to about 10% by weight of at least one acid fluoride salt selected from ammonium bifluoride, sodium bifluoride, potassium bifluoride, calcium fluorophosphates, sodium fluorosilicates, and combinations of two or more thereof;   from about 2% to about 20% by weight of at least one mineral acid adduct with urea;   from about 1% to about 10% by weight at least one surfactant; and   from about 1% to about 10% by weight at least one organic solvent.   
     
     
         13 . The aqueous cleaning composition of  claim 12  comprising:
 from about 1% to about 10% by weight of ammonium bifluoride; 
 from about 2% to about 20% by weight of at least one mineral acid adduct with urea selected from the adducts of urea with perchloric acid; hydroiodic acid; hydrobromic acid; hydrochloric acid; sulfuric acid; nitric acid; phosphoric acid and combinations of two or more thereof; 
 from about 1% to about 10% by weight at least one surfactant; and 
 from about 1% to about 10% by weight at least one organic solvent. 
 
     
     
         14 . A method of cleaning a metal surface, the method comprising:
 contacting the metal surface with an aqueous cleaning composition for a sufficient time to clean the metal surface, the aqueous cleaning composition comprising:
 at least one acid fluoride salt selected from ammonium bifluoride, sodium bifluoride, potassium bifluoride, calcium fluorophosphates, sodium fluorosilicates, and combinations of two or more thereof; 
 at least one mineral acid adduct with urea; 
 at least one surfactant; and 
 at least one organic solvent. 
   
     
     
         15 . The method of  claim 14  wherein the acid fluoride salt is ammonium bifluoride. 
     
     
         16 . The method of  claim 14  wherein the mineral acid adduct with urea is selected from among the adducts of urea with perchloric acid; hydroiodic acid; hydrobromic acid; hydrochloric acid; sulfuric acid; nitric acid; phosphoric acid and combinations of two or more thereof. 
     
     
         17 . A method of cleaning a metal surface, the method comprising:
 contacting the metal surface with an aqueous cleaning composition for a sufficient time to clean the metal surface, the aqueous cleaning composition comprising:
 from about 1% to about 10% by weight of at least one acid fluoride salt selected from ammonium bifluoride, sodium bifluoride, potassium bifluoride, calcium fluorophosphates, sodium fluorosilicates, and combinations of two or more thereof; 
 from about 2% to about 20% by weight of at least one mineral acid adduct with urea; 
 from about 1% to about 10% by weight at least one surfactant; and 
 from about 1% to about 10% by weight at least one organic solvent. 
   
     
     
         18 . The method of  claim 17  wherein the mineral acid adduct with urea is selected from among the adducts of urea with perchloric acid; hydroiodic acid; hydrobromic acid; hydrochloric acid; sulfuric acid; nitric acid; phosphoric acid and combinations of two or more thereof.