Nano-Silica Based Sol-Gel Coating of Direct Dyed Cotton Fabric to Improve the Colorfastness Properties

Abstract

This research was aimed to achieve the better washing fastness of direct dyes using sol-gel after treatment. Early work indicates that the after treatments used to improve the wash fastness were affect the hue, rubbing and light fastness of direct dye and were environmentally hazardous because of containing formaldehyde and copper salts. The present process consists of simple pad-dry-cure method which is optimized. The prime focus of using sol-gel after-treatment is to make better wash fastness without affecting the properties discussed above. A series of nanosols were prepared from the selected silane derivatives, which were then applied on dyed cotton samples. Different tests were conducted on coated samples and compared to control. This method shows tremendous effect of increasing the washing fastness of direct dyes on cotton without essential loss of properties, such as hue, rubbing, light fastness and handle of the fabric.