Why is polyester often added to cotton cloth, even if only in tiny few percentage quantities?

Question

I often see on clothes, bags, sheets, etc. a few % of polyester in the cotton cloth label. What does this mean and why do they do it? Are they weaving one out of every few strands out of polyester? Or is the fiber itself made of a few % polyester in composition? And what does it do for the cloth?

In: 1242

Answer 1

after years of ruined shirts and lying ass companies claiming their cotton was pre-shrunk when it wasn’t, I now look for a small percentage of some synthetic fiber, because that way I know it won’t shrink

So maybe that’s why