Shrinkage is the contraction in the dimension of the fabric due to usage. Cotton fabric suffers from two main disadvantages of shrinking and creasing during subsequent washing. Creasing is overcome by the resin finishing, whereas the shrinking is prevented by a special finishing known as sanforizing, and the machine used for that purpose is known as Zero-Zero preshrinking.

Evaluation Methodology

The chemically treated knitted fabric is tested for dimensional stability, spirality, bursting strength, and formaldehyde content as per the standard test methods as mentioned below:

Dimensional Change after Washing

This test method is used to determine the dimensional changes in woven and knitted fabrics made of fibers other than wool when subjected to laundering procedures commonly used in commercial laundry. A range of laundering procedures from severe to mild is provided to allow simulation of the various types of launderings available. Five drying test procedures are established to cover the drying techniques used. These tests are not accelerated and must be repeated to determine dimensional changes after multiple launderings.

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The authors are associated with the Dept. of Textile Technology PSG College of Technology, Coimbatore.

Originally published in Textile Review, January-2012.