Treatment of textile material

Abstract

The present invention generally relates to a method for changing the color of a textile material to obtain a vintage and/or worn appearance comprising the steps of contacting said fabric textile material with a nitrate salt, activating the nitrate salt by the addition of an acid catalyst until the desired color change is achieved.

1 . A method for changing the color of a dyed textile material to obtain a vintage and/or worn appearance comprising the steps of:
 (a) contacting said textile material with at least one nitrate salt selected from the group consisting of KNO 3 , Ca(NO 3 ) 2 , NaNO 3 , Mg(NO 3 ) 2 , and Al(NO 3 ) 3 ,   (b) activating said nitrate salt by the addition of an acid catalyst, selected from the group consisting of sulfates, phosphates, sulfonic acids, carboxylic acids and mineral acids, and   (c) maintaining step (b) until a desired color change is achieved,   wherein steps (a)-(c) are conducted at a temperature below 90° C.   
     
     
         2 . The method according to  claim 1 , wherein steps (a)-(c) are carried out at a temperature of 60-90° C. 
     
     
         3 . The method according to  claim 1 , wherein the acid catalyst is selected from the group consisting of sodium persulfate (Na 2 S 2 O 8 ), potassium persulfate (K 2 S 2 O 8 ), sodium phosphate, potassium phosphate, phosphoric acid, methanesulfonic acid, toluenesulfonic acid, tartaric acid, and malonic acid. 
     
     
         4 . The method according to  claim 1 , wherein a ΔL value between the denim textile material before step (a) and after step (c) is greater than 2, wherein L refers to lightness as defined by CIE 1976 Lab color space. 
     
     
         5 . The method according to  claim 1 , wherein the nitrate salt and acid catalyst are provided in an aqueous solution. 
     
     
         6 . The method according to  claim 5 , wherein the solution comprises 1-75 vol % of the nitrate salt. 
     
     
         7 . The method according to  claim 6 , wherein the solution comprises 4-60 vol % of the nitrate salt. 
     
     
         8 . The method according to  claim 5 , wherein the solution comprises 0.1-50 vol % of the acid catalyst. 
     
     
         9 . The method according to  claim 8 , wherein the solution comprises 0.5-25 vol % of the acid catalyst. 
     
     
         10 . The method according to  claim 5 , wherein the solution further comprises 0.01-15 vol % of at least one auxiliary agent. 
     
     
         11 . The method according to  claim 5 , wherein the pH of the solution is higher than 2. 
     
     
         12 . The method according to  claim 1 , further comprising contacting said textile material with an auxiliary agent. 
     
     
         13 . The method according to  claim 1 , wherein the dyed textile material is dyed with a dye selected from the group consisting of a sulphur dye, a reactive dye, a direct dye, a VAT dye, a basic dye, a pigment dye, a natural dye, and a combination of two or more of the foregoing. 
     
     
         14 . The method according to  claim 1 , further comprising the step of applying a laser beam to the textile material to generate NOx compounds. 
     
     
         15 . The method of  claim 9 , wherein the laser beam consists of infrared light or light having a wavelength of 10.6 μm.