"How often is a spot removed with cleaning only to reappear upon drying? Many cleaners would say it is their number one complaint. Others would also say that they do not have a guaranteed system to stop that same spot from reappearing again and again. This is called a “wicking spot.”
How wicking spots are different
Wicking spots are different in that the material in the spot has collected at the tips of the fibers. Other types of spots are likely to travel the entire depth of the yarn. This kind of spot is also different because the liquids have penetrated into the carpet backing or even to the substrate. Thus, wicking spots are more likely to have moisture readings prior to cleaning. This means one can discover them before cleaning.
Another thing to note is that they are more likely to occur on hydrophobic fibers such as polypropylene/olefin, triexta and polyester; however, it still happens on nylon."
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