Stain removal through novel oxidizer and chelant combination

Abstract

The present invention relates to a detergent composition comprising alkali metal carbonate, a chelant selected from the group consisting of MGDA, alkali metal tripolyphosphate, GLDA, and mixtures thereof, alkali metal percarbonate, and a peroxidation catalyst, wherein the molar ratio of chelant to alkali metal percarbonate is in the range of 1.8 to 3.4. The detergent composition is particularly suited for the removal of tea and coffee stains.

1 : A detergent composition comprising:
 alkali metal carbonate,   as a chelant methylglvcinediacetic acid and optionally glutamic acid diacetic acid and/or alkali metal tripolyphosphate,   alkali metal percarbonate, and   a peroxidation catalyst according to the formula   
       
         
           
           
               
               
           
         
         wherein 
         L 1  and L 2  can either be separate ligands or where L 1  and L 2  can combine to be a single molecule, each L independently is an organic ligand containing at least three nitrogen atoms that coordinate with the metal M; 
         M is Mn or Fe; 
         each X independently is a coordinating or bridging group selected from the group consisting of H 2 O, OH − , SH − , HO 2   − , O 2- , O 2   2- , S 2- , F − , Cl − , Br − , I − , NO 3   − , NO 2   − , SO 4   2- , SO 3   2- , PO 4   3- , N 3   − , CN − , NR 3 , NCS − , RCN, RS − , RCO 2   − , RO − , and 
       
       
         
           
           
               
               
           
         
       
       with R being hydrogen or a C 1  to C 6  alkyl group;
 Y is a counter ion; 
 wherein the molar ratio of chelant to alkali metal percarbonate is in the range of 1.8 to 3.4; 
 wherein said molar ratio is calculated based on the total molar amount of methylglvcinediacetic acid, glutamic acid N,N-diacetic acid, and alkali metal tripolyphosphate; 
 wherein for the purpose of calculating said molar ratio alkali metal percarbonate is assumed to have the formula 2(M2CO3).3H2O2, where M represents an alkali metal; 
 and wherein the total amount of methylglycine diacetic acid, glutamic acid N,N-diacetic acid and alkali metal tripolyphosphate is not more than 35% by weight. 
 
     
     
         2 : The detergent composition according to  claim 1 , wherein the detergent composition comprises as a chelant MGDA, GLDA and an alkali metal tripolyphosphate. 
     
     
         3 . (canceled) 
     
     
         4 : The detergent composition according to  claim 1 , comprising at most 28% by weight alkali metal tripolyphosphate. 
     
     
         5 : The detergent composition according to  claim 1 , wherein the composition comprises 5 to 30% by weight alkali metal percarbonate. 
     
     
         6 : The detergent composition according to  claim 1 , wherein the composition provides a pH of at least 8 when diluted in distilled water at a concentration of 1 g/l. 
     
     
         7 . (canceled) 
     
     
         8 : The detergent composition according to  claim 1 , wherein L is a ligand according to formulae (II) to (IV) 
       
         
           
           
               
               
           
         
       
       wherein each R 1  is independently selected from the group consisting of hydrogen and C 1 -C 6  alkyl. 
     
     
         9 : The detergent composition according to  claim 1 , wherein Y is selected from the group consisting of Cl − , Br − , I − , NO 3   − , ClO 4   − , NCS − , BPh 4   − , BF 4   − , PF 6   − , R 2 —SO 3   − , R 2 —SO 4   − , and R 2 —CO 2   − , wherein R 2  is hydrogen or a C 1  to C 4  alkyl group. 
     
     
         10 : The detergent composition according to  claim 1 , wherein the composition comprises 0.0005 to 0.12% by weight of the metal M in the form of a peroxidation catalyst complex. 
     
     
         11 : The detergent composition according to  claim 1 , wherein the composition further comprises at least one additional compound comprising surfactants, activating agents, additional chelating/sequestering agents, silicates, detergent fillers or binding agents, defoaming agents, anti-redeposition agents, enzymes, dyes, odorants, or mixtures thereof. 
     
     
         12 : The detergent composition of  claim 1 , further comprising 1.5 to 5% by weight nonionic surfactant. 
     
     
         13 : The detergent composition of  claim 1 , further comprising 0.1 to 5% by weight additional chelating/sequestering agents. 
     
     
         14 : A method of using a detergent composition comprising:
 providing the detergent composition according to  claim 1  as a warewashing detergent for the removal of tea and coffee soil.   
     
     
         15 : The method according to  claim 14 , wherein the detergent composition is diluted to provide a use solution with a concentration of 0.1 to 10 g/l. 
     
     
         16 : The method according to  claim 14 , wherein the detergent composition is used at a temperature of 20 to 85° C.