Mercerized

http://www.classiceliteyarns.com/WebLetter/Yarns/Mercerized.php

Classic Elite has kindly answered my question in their web letter that came out today. I'm now quoting from them:

What does Mercerized mean?
Mercerized cotton has a beautiful luster—the result of a treatment that reduces the natural fuzz along the fiber’s length. The process smoothes the surface of the yarn and in addition to providing sheen it also increases cotton’s ability to absorb dye. The rich saturation of color in mercerized cottons are a dream for the textile artist who revels in beautiful color.