Bis-Azo Colorants For Use As Bluing Agents

Abstract

This invention relates to bis-azo colorants for use as bluing agents, laundry care compositions comprising bis-azo colorants that may serve as bluing agents, processes for making such bluing agents and laundry care compositions and methods of using the same. The bluing agents are generally comprised of at least two components: at least one chromophore component and at least one polymeric component. These bluing agents are advantageous in providing a whitening effect to fabrics, while not building up over time and causing undesirable blue discoloration to the treated fabrics.

We claim: 
     
         1 . A bluing agent comprising:
 (a) at least one chromophore component that comprises a bis-azo colorant, and   (b) at least one polymeric component selected from a polyalkyleneoxy and a capped polyalkyleneoxy;   wherein said chromophore and said polymeric component are covalently bound to one another and wherein the bluing agent is selected from the following structures:   
       
         
           
           
               
               
           
         
       
       and
 mixtures thereof; 
 wherein R 1  is selected from H, alkyl, hydroxyalkyl, polyalkyleneoxy and a capped polyalkyleneoxy; R 2  and R 3  are independently selected from the group consisting of H, alkyl, alkoxy, alkyleneoxy, capped alkyleneoxy, polyalkyleneoxy and capped polyalkyleneoxy; R 4  is selected from H, C(O)H and C(O)R 5 ; wherein R 5  is independently selected from the group consisting of C 1-7  alkyl, C 6-10  aryl, and C 7-11  arylalkyl; wherein said capping groups are independently selected from C(O)R 5  and R 5 ; wherein the A ring may be further substituted with one or more groups selected from the group consisting of C 1-8  alkyl, C 1-8  alkoxy, nitro and OR 6 ; wherein R 6  is selected from the group consisting of H, hydroxyalkyl, a polyalkyleneoxy and a capped polyalkyleneoxy; wherein each M is independently selected from the group consisting of an alkali metal cation, an ammonium ion and an alkaline earth metal cation. 
 
     
     
         2 . A bluing agent according to  claim 1  in which in the bluing agent R 2  and R 3  are independently selected from the group consisting of H, alkyl, alkoxy, alkyleneoxy, and capped alkyleneoxy. 
     
     
         3 . A bluing agent according to  claim 1  in which in the bluing agent, R 2  and R 3  are independently selected from the group consisting of H, C 1-4  alkyl, and C 1-4  alkoxy. 
     
     
         4 . A bluing agent according to  claim 1  in which in the bluing agent, IV is a polyoxyalkylene chain having from 2 to 100 repeating units. 
     
     
         5 . A bluing agent according to  claim 4  in which in the bluing agent, R 1  is a polyoxyalkylene chain having from 4 to 50 repeating units. 
     
     
         6 . A bluing agent according to  claim 5 , wherein the polyoxyalkylene chain comprises ethyleneoxide for at least 50% of the units. 
     
     
         7 . A bluing agent according to  claim 1  wherein the bluing agent's chromophore exhibits an absorbance spectrum maximum in water of from about 560 nanometers to about 640 nanometers. 
     
     
         8 . A bluing agent according to  claim 1  wherein the bluing agent exhibits an absolute hue angle in the range of 220° to 320°, preferably from 240° to 310°, more preferably from 250° to 300°. 
     
     
         9 . A bluing agent according to  claim 5  wherein R 2  is alkyl and R 3  is selected from C 1-4  alkyl and C 1-4  alkoxy groups. 
     
     
         10 . A bluing agent according to  claim 5  wherein R 2  and R 3  are C 1-4  alkoxy groups. 
     
     
         11 . A bluing agent according to  claim 9 , wherein R 4  is H or C(O)CH 3 . 
     
     
         12 . A bluing agent according to  claim 10 , wherein R 4  is H or C(O)CH 3 . 
     
     
         13 . A bluing agent according to  claim 3 , wherein the A ring is substituted with another group selected from alkyl, alkoxy and OR 1 .