Ink comprising dispersed nanopigment micelles and printed textiles obtained therefrom

Abstract

The present invention provides a water-based ink comprising nanopigment micelles, said nanopigment micelles comprising a pigment particle and a polymeric dispersing agent around said pigment particle, whereby said pigment particles have an average particle size between 100 nm and 250 nm. The invention also relates to a printed textile and a dyeing and printing process using said water-based ink.

1 . A water-based ink comprising:
 nanopigment micelles ( 1 ), said nanopigment micelles ( 1 ) comprising a pigment particle ( 1   a ) and a polymeric dispersing agent ( 1   b ), wherein said pigment particles ( 1   a ) have an average particle size between 150 nm and lower than 200 nm, as determined by ISO 13320:2009;   a binder polymer ( 2 );   wherein said polymeric dispersing agent ( 1   b ) is a block copolymer comprising at least one hydrophilic segment comprising a homo- or co-polyether block amide and at least one hydrophobic segment comprising a homo- or co-polyether block amide, and   wherein said nanopigment micelles are comprised in an amount of 40 wt. % to 60 wt. %, of said pigment particles ( 1   a ) and of 60 wt. % to 40 wt. % of said polymeric dispersing agent ( 1   b ).   
     
     
         2 . Water-based ink according to  claim 1 , wherein said block copolymer is selected from the group consist of a polyvinyl ether, a polyether block amide, a polyoxazoline and a copolyamide 
     
     
         3 . Water-based ink according to  claim 1 , comprising 1 to 15 wt. % of organic solvent based on the total weight of the ink. 
     
     
         4 . Water-based ink according to  claim 1 , comprising water in an amount of 80 to 98 wt. % based on the total weight of the ink. 
     
     
         5 . Water-based ink according to  claim 1 , comprising the binder polymer ( 2 ) in an amount of 0.5 to 5 wt. %, relative to the total amount of said water-based ink. 
     
     
         6 . Water-based ink according to  claim 1 , wherein said pigment particles ( 1   a ) have an average particle size of 150 nm to 170 nm. 
     
     
         7 . Water-based ink according to  claim 1 , wherein said polymeric dispersing agent ( 1   b ) is disposed around said pigment particle ( 1   a ). 
     
     
         8 . Water-based ink according to  claim 1 , wherein said hydrophilic segment is located at a terminal of the polymer chain. 
     
     
         9 . Water-based ink according to  claim 1 , wherein said binding polymer comprises 0 wt. % to less then 1.0 wt. %. relative to the total amount of said water-based ink. 
     
     
         10 . Water-based ink according to  claim 1 , wherein said water-based ink has a viscosity of 2 mPa·s to 14 mPa·s as determined with a Brookfield viscometer at 25° C. 
     
     
         11 . Water-based ink according to  claim 1 , wherein said water-based ink has a pH of 7 to 9 at 25° C. 
     
     
         12 . A method for preparing a water-based ink according to  claim 1 , comprising the steps of:
 i. high shear mixing of pigment particles ( 1   a ) having an average particle size between 150 nm and lower than 200 nm, as determined by ISO 13320:2009, and a polymeric dispersing agent ( 1   b ) in water, thereby obtaining nanopigment micelles ( 1 ); and   ii. adding water to said nanopigment micelles ( 1 ), thereby obtaining a water-based ink.   
     
     
         13 . Method according to  claim 12 , whereby a pigment is wet grinded to said pigment particles ( 1   a ) in presence of water prior to high shear mixing. 
     
     
         14 . A method for printing a textile material ( 3 ), comprising the steps of:
 i. applying a water-based ink according to  claim 1  onto a textile material ( 3 ), and   ii. fixating said water-based ink onto said textile material ( 3 ) by drying.   
     
     
         15 . Method according to  claim 14 , wherein said textile material ( 3 ) is not pre-treated before step i. 
     
     
         16 . Method according to  claim 15 , wherein said textile material ( 3 ) is not rinsed after step i. 
     
     
         17 . Pigmented textile ( 3 ) according to  claim 14 , wherein said textile ( 3 ) is selected from the group consisting of wool, cotton, silk, polypropylene, polyester and nylon.