Process for selective decolorizating fabric

Abstract

A process for removing dye and improving hand in cellulosic textiles utilizing a mercerizing ozone bath. The process also prevents redeposit of dye which is residual in a dyeing process. The time and temperature of the process is dependent upon the type of dye and the temperature the process is run. The process can be used in vat dyeing, jet dyeing, package dyeing and the like to obtain different shades of color while improving the hand and luster of the textile.

1 . A process for selectively mercerizing and decolorizing a colorant or mercerized post dyed cellulose containing textile goods which comprises treating the textile goods with ozone at temperature of about 50-120° F. in an alkaline bath for a period of time to mercerize the textile goods and to remove or decolorize a colorant of the textile goods. 
     
     
         2 . The process of  claim 1  wherein a gas comprising ozone is bubbled into said bath containing said textile goods. 
     
     
         3 . The process of  claim 1  wherein said bath is ozone enriched prior to the addition of said textile goods. 
     
     
         4 . The process of  claim 1  wherein said textile goods comprise synthetic fibers which are plated with colorant. 
     
     
         5 . The process of  claim 1  wherein the period of time is at least 3 minutes. 
     
     
         6 . The process of  claim 5  wherein the period of time is between 3 and 20 minutes. 
     
     
         7 . The process of  claim 1  wherein said textile goods comprises a polyester, the bath is at a temperature of between 50° and 120° F. and the textile goods is treated with ozone in said bath for a period of about 3 to 5 minutes. 
     
     
         8 . The process of  claim 1  wherein said textile goods is cotton, the colorant is a direct or reactive dye, the temperature of the bath is about 100° F., and the textile goods are treated with ozone in said bath for about 3 to 20 minutes. 
     
     
         9 . A process for preventing the redeposit of a colorant on a textile substrate in an aqueous bath in which the textile substrate is to be placed which comprises pre-treating said bath with ozone whereby any colorant in said bath is oxidized or decolorized prior to the addition of said textile substrate. 
     
     
         10 . The process of  claim 9  wherein said bath is subsequently used to decolorize a dyed textile substrate. 
     
     
         11 . The process of  claim 9  wherein ozone or ozone and air is bubbled into said bath.