An odd question, but having scanned through many of my cels, I don't think I have any that feature characters with curly hair.
In fact as far as anime characters go, I don't care for those with curly hair but much prefer straight. In reality that's not the case because girls with curly hair often look very attractive.
I think what alters my perception is the fact that anime can't create effective texture or detail. So, unless it's particularly stylized, curly hair in anime looks a real mess.