If you have ever purchased a 100% cotton shirt before you know there are often problems associated with this fabric. The colors fade and become dull, the fabric shrinks, and after a few times of wearing and washing you can see millions of little fuzzies over the surface of your shirts. The process of Mercerization makes all these little annoyances go away. Single Mercerization is a process in which the yarn used to make a shirt is run through the middle of an open flame at a very high speed. .