"http://www.youtube.com/watch?v=Vhpq7-c911A Here is the link. He called it "boiling" or "chatter" effect. You can see it in Coraline when there is a close up shot of her pants. I'm sure certain fabric performed better…"
"Another issue to consider: Real fabric will cause "noise" when shot because of the fabric hair shifted each time it is touch. Travis Knight of Laika explained how they solve it by coating the fabric with transparent silicone. "