Acidic Cleaning Compositions

Abstract

A composition comprising a mixing product of: (i) a first acid having a pKa of less than 3, in an amount by weight of 1-10%, (ii) a second acid having a pKa of greater than 3, in an amount by weight of 1-10%, (iii) a nonionic surfactant in an amount by weight of 1-7%; and (vi) water; wherein the composition has a pH of less than 2.5. The composition can be used for the removal of grease, lime scale, soap scum and rust on hard surfaces.

1 . A composition comprising a mixing product of: 
 (i) a first acid having a pKa of less than 3, in an amount by weight of 1-10%,    (ii) a second acid having a pKa of greater than 3, in an amount by weight of 1-10%,    (iii) a nonionic surfactant in an amount by weight of 1-7%; and    (vi) water;    wherein the composition has a pH of less than 2.5.    
   
   
       2 . The composition of  claim 1  wherein the first acid is phosphoric acid.  
   
   
       3 . The composition of  claim 1 , wherein the second acid is lactic acid.  
   
   
       4 . The composition of  claim 1 , wherein the nonionic surfactant comprises a polyethoxylated alcohol.  
   
   
       5 . The composition of  claim 1 , wherein the nonionic surfactant comprises a mixture of molecules of formula I; CH 3 (CH 2 ) m —(O—CH 2 —CH 2 ) n —OH, wherein m is 8-10, and n represents an average degree of ethoxylation for the mixture of 1-15.  
   
   
       6 . The composition of  claim 1  further comprising an anionic surfactant.  
   
   
       7 . The composition of  claim 6 , wherein the anionic surfactant comprises an alkylaryl sulfonate surfactant.  
   
   
       8 . The composition of  claim 6 , wherein the anionic surfactant comprises sodium cumene sulfonate.  
   
   
       9 . The composition of  claim 1  further comprising an organic solvent selected from the group consisting of alkanols, glycol ethers, glycol diethers, and mixtures thereof.  
   
   
       10 . The composition of  claim 1  further comprising a 1:1:1 mixture by weight of ethanol, dipropylene glycol monobutyl ether, and propylene glycol n-butyl ether.  
   
   
       11 . The composition of  claim 1 , wherein the amount by weight of the first acid is 2-5%.  
   
   
       12 . The composition of  claim 1  wherein the amount by weight of the second acid is 2-5%.  
   
   
       13 . The composition of  claim 4 , wherein the amount by weight of anionic surfactant is 0.1-8%.  
   
   
       14 . The composition of  claim 1 , wherein any cationic surfactant is present in an amount of less than 0.5% by weight.  
   
   
       15 . The composition of  claim 1  further comprising sodium hydroxide.  
   
   
       16 . The composition of  claim 15 , wherein the amount by weight of sodium hydroxide is up to 1%.  
   
   
       17 . The composition of  claim 1 , wherein the composition comprises: 
 (i) phosphoric acid in an amount by weight of 2.5-3.5%;    (ii) lactic acid in an amount by weight of 2.5-3.5%;    (iii) surfactant in an amount by weight of 3-5% comprising 
 (a) compounds of formula I: CH 3 (CH 2 ) m —(O—CH 2 —CH 2 ) n —OH wherein m is an integer of 8 to 10, and wherein the average degree of ethoxylation, n, is 2 to 10, and  
 (b) sodium cumene sulfonate;  
   (iv) an organic solvent in an amount by weight of about 3% comprising a 1:1:1 mixture by weight of ethanol, dipropylene glycol monobutyl ether, and propylene glycol n-butyl ether; and    (v) water;    wherein the composition has a pH of 1-2.    
   
   
       18 . A non-aerosol container containing the composition of  claim 1  and having a spray pump to dispense the composition.  
   
   
       19 . The non-aerosol container of  claim 18 , wherein the spray pump is a foam-generating pump, so that the composition can be dispensed in the form of a foam.  
   
   
       20 . A method of removing grease, lime scale, soap scum and rust from a hard surface comprising the step of applying the composition of  claim 1  onto the hard surface, and rinsing the hard surface.