Optimized release of bleaching systems in laundry detergents

Abstract

The need for a stable, safe on fabric, bleaching laundry detergent, that is also convenient to use, can be met by incorporating an aryliminium cation and/or zwitterion, and an activated peroxygen source, into fluid portions of a unit dose laundry detergent article. Such unit dose articles also result in reduced damage from bleach spotting.

1 . A unit dose laundry detergent article comprising:
 a) a surfactant selected from anionic, nonionic surfactant, and mixtures thereof; and   b) a bleaching system comprising:
 (i) an organic bleach catalyst comprising of an aryliminium ion selected from the group consisting of: cations, zwitterions, and mixtures thereof; and 
 (ii) an activated peroxygen source selected from the group consisting of: a preformed peracid; a hydrogen peroxide source; and mixtures thereof; 
   enclosed in a water-soluble, wherein: at least about 50% by weight of the anionic and/or nonionic surfactant, and at least about 50% by weight of the aryliminium ions are comprised in at least one fluid composition.   
     
     
         2 . The unit dose laundry detergent article according to  claim 1 , wherein the aryliminium ion is a zwitterion having the structure selected from the group consisting of:
 c)   
       
         
           
           
               
               
           
         
         wherein: in (Formula 1),
 (i) R 1  is selected from the group consisting of: H, a branched alkyl group containing from 3 to 24 carbons, and a linear alkyl group containing from 1 to 24 carbons; preferably, R 1  is a branched alkyl group comprising from 6 to 18 carbons, or a linear alkyl group comprising from 5 to 18 carbons, more preferably each R 1  is selected from the group consisting of: 2-propylheptyl, 2-butyloctyl, 2-pentylnonyl, 2-hexyldecyl, n-hexyl, n-octyl, n-decyl, n-dodecyl, n-tetradecyl, n-hexadecyl, n-octadecyl, iso-nonyl, iso-decyl, iso-tridecyl and iso-pentadecyl; 
 (ii) R 2  is independently selected from the group consisting of: H, a branched alkyl group comprising from 3 to 12 carbons, and a linear alkyl group comprising from 1 to 12 carbons; preferably R 2  is independently selected from H and methyl groups; 
 (iii) n is an integer from 0 to 1; 
 
         d) 
       
       
         
           
           
               
               
           
         
         
           3-(3,4-dihydroisoquinolinium)propane sulfonate; 
         
         c) and mixtures thereof. 
       
     
     
         3 . The unit dose laundry detergent article according to  claim 2  comprising an aryliminium ion of structure (1), wherein R 2  is H and n is 1, such that the aryliminium ion is a zwitterion having the structure: 
       
         
           
           
               
               
           
         
         wherein: in Formula 3, 
         R 1  is a branched alkyl group containing from 9 to 24 carbons or linear alkyl group containing from 11 to 24 carbons, preferably each R 1  is a branched alkyl group containing from 9 to 18 carbons or linear alkyl group containing from 11 to 18 carbons, more preferably each R 1  is selected from the group consisting of 2-propylheptyl, 2-butyloctyl, 2-pentylnonyl, 2-hexyldecyl, n-dodecyl, n-tetradecyl, n-hexadecyl, n-octadecyl, iso-nonyl, iso-decyl, iso-tridecyl and iso-pentadecyl. 
       
     
     
         4 . The unit dose laundry detergent article according to  claim 1 , wherein the aryliminium ion is a cation having the structure: 
       
         
           
           
               
               
           
         
         wherein: in Formula 4, 
         (i) R 3  is independently selected from the group consisting of: H and methyl groups; preferably, R 3  is H; 
         (ii) R 4  and R 5  are independently selected from the group consisting of: H, a branched alkyl group containing from 3 to 12 carbons, and a linear alkyl group containing from 1 to 12 carbons; preferably, R 4  and R 5  are H or methyl, more preferably, R 4  and R 5  are H; 
         (iii) X −  is a charge-balancing counterion; preferably a bleach-compatible counterion; 
       
     
     
         5 . The unit dose laundry detergent article according to  claim 1 , wherein the activated peroxygen source is a preformed peracid selected from the group consisting of: phthalimido peroxycaproic acid (PAP), percarboxylic acids and salts, percarbonic acids and salts, perimidic acids and salts, peroxymonosulphuric acids and salts, and mixtures thereof. 
     
     
         6 . The unit dose laundry detergent article according to  claim 5 , comprising a fluid comprising compartment containing a preformed peracid, wherein the fluid has a neat pH of from about 4 to about 10. 
     
     
         7 . The unit dose laundry detergent article according to  claim 6 , wherein the fluid has a neat pH of from about 6.5 to about 9. 
     
     
         8 . The unit dose laundry detergent article according to  claim 7 , wherein the fluid has a neat pH of from about 7 to about 8.5. 
     
     
         9 . The unit dose laundry detergent article according to according to  claim 1 , wherein the fluid comprising compartment that contains the aryliminuim ion, wherein the fluid has a neat pH of less than about 9. 
     
     
         10 . The unit dose laundry detergent article according to according to  claim 9 , wherein the fluid has a neat pH of less than about 8.5. 
     
     
         11 . The unit dose laundry detergent article according to according to  claim 10 , wherein the fluid has a neat pH of less than about 8. 
     
     
         12 . The unit dose laundry detergent article according to according to  claim 11 , wherein the fluid has a neat pH of less than about 7. 
     
     
         13 . The unit dose laundry detergent article according to  claim 1 , wherein the activated peroxygen source is a hydrogen peroxide source selected from the group consisting of: a peroxide; a persalt; and mixtures thereof. 
     
     
         14 . The unit dose laundry detergent article according to  claim 13 , further comprising a bleach activator. 
     
     
         15 . The unit dose laundry detergent article according to  claim 14 , wherein the bleach activator is selected from the group consisting of: nonanoyloxybenzene sulphonate (NOBS), sodium 4-(isononanoyloxy)benzenesulphonate (iso-NOBS), tetraacetyl ethylene diamine (TAED) or mixtures thereof. 
     
     
         16 . The unit dose laundry detergent article according to  claim 15 , wherein the bleach activator is sodium 4-(isononanoyloxy)benzenesulphonate (iso-NOBS), and the unit dose laundry detergent article further comprises a lipase enzyme. 
     
     
         17 . The unit dose laundry detergent article according to  claim 1 , further comprising perfume microcapsules, wherein the perfume microcapsule wall material preferably comprises: melamine crosslinked with formaldehyde, polyurea, urea crosslinked with formaldehyde, or urea crosslinked with gluteraldehyde. 
     
     
         18 . The unit dose laundry detergent article according to  claim 1 , wherein part of the peroxygen source is physically separated from the aryliminium ions by a means selected from the group consisting of:
 a) at least about 50% by weight of the activated peroxygen source being a solid;   b) at least about 50% by weight of the activated peroxygen source being encapsulated by a water-soluble or dispersible barrier; and   c) at least about 50% by weight of the activated peroxygen source being in a different compartment comprising less than about 25% by weight of the aryliminium ions.   
     
     
         19 . The unit dose laundry detergent article according to  claim 1 , further comprising a detersive enzyme selected from the group consisting of: lipase, protease, amylase, cellulase, pectate lyase, xyloglucanase, and mixtures thereof; wherein at least part of the peroxygen source is physically separated from the detersive enzyme by a means selected from the group consisting of:
 a) at least about 50% by weight of the activated peroxygen source being a solid;   b) at least about 50% by weight of the activated peroxygen source being encapsulated by a water-soluble or dispersible barrier; and   c) at least about 50% by weight of the activated peroxygen source being in a different compartment comprising less than about 25% by weight of the detersive enzymes.   
     
     
         20 . The unit dose laundry detergent article according to  claim 1 , further comprising a perfume; wherein at least part of the peroxygen source is physically separated from the perfume by a means selected from the group consisting of:
 a) at least about 50% by weight of the activated peroxygen source being a solid;   b) at least about 50% by weight of the activated peroxygen source being encapsulated by a water-soluble or dispersible barrier; and   c) at least about 50% by weight of the activated peroxygen source being in a different compartment comprising less than about 25% by weight of the perfume.   
     
     
         21 . A unit dose laundry composition according to  claim 1 , wherein the water-soluble or dispersible film comprises: polyvinyl alcohol, polyvinyl alcohol copolymers, or mixtures thereof.