ARS | Publication request: DCCA SHRINKPROOFING OF WOOL - PART II: IMPROVING WHITENESS AND SURFACE PROPERTIES

Submitted to: Textile Research Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 29, 2003
Publication Date: July 1, 2004
Citation: Cardamone, J.M., Yao, J. 2004. DCCA shrinkproofing of wool - part II: improving whiteness and surface properties. Textile Research Journal. 74(7):565-570.

Interpretive Summary: Wool fabrics lose whiteness when chlorinated for shrinkage control. Further processing causes pilling, the interlocking of fiber ends on the fabric surface. Alleviating shrinkage while maintaining whiteness and a uniform fabric surface that resists pilling will lead to increasing wool's marketability. We improved the traditional chlorination process by applying dichlorodicyanuric acid (DCCA) for control shrinkage, hydrogen peroxide for whiteness, and gluconic acid (GA) for improvement in fabric hand. Shrinkage was controlled to 1% without sacrificing mechanical strength and stretchability. Only the fiber surface was affected. The fabric showed greater pliability and less surface friction. Fabrics treated with GA and DCCA followed by hydrogen peroxide exhibited good pilling resistance. This process can alleviate the need to import chlorinated wool and will provide the textile mill with a more efficient procedure to eliminate subsequent steps to whiten and improve hand.

Technical Abstract: We reported in Part I that when wool fabric is treated with dichloroisocyanuric acid (DCCA) to control shrinkage, fabric yellowness develops. Now, in a modified process, DCCA, gluconic acid (GA), and hydrogen peroxide are applied to limit shrinkage to 1% and maintain whiteness. This process affects only the outer scales of wool. The fabric hand of the fabrics also improves. Fabric strength and elongation at break remain unchanged while the modulus (stiffness) decreases to indicate a more pliable fabric has been produced. The results of low-deformation mechanical properties showed that fabrics treated with GA and DCCA in step 1 and peroxide alone in step 2 exhibit a more uniform surface that resists pilling. This chlorine-free process should be readily accepted because it can be used without additional processing to whiten and improve the fabric hand.