I have used Sharpies for lots of fabric applications. Some of the colors, especially the reds, can bleed. And yes, I have even made quilt labels with them. (Don't tell the quilt police). I do avoid the reds, of course. I heat set with a HOT iron and always hand wash the label separately before attaching it to the quilt, just in case. I've never had any major problems. The lighter colors do tend to fade somewhat with washing. None of my quilts are much more than 10 years old, but the labels I've made that way are still very colorful and completely legible.