Micron pens are so-so. There was a post here a while ago about using pens for signature quilts. It referenced Peckish's blog where she tested a bunch of pens:
http://www.seamstobeyouandme.com/ You'll need to scroll down a couple posts to November 15, 2015 for "The Great Signature Pen Debate" post.
Personally, I prefer Inktense pencils, but you need to set those with a medium & wait for 7 days before washing. You can use aloe or fabric medium. I've found that fabric medium gives slightly more saturated results. A little goes a long way. They sell 3 oz bottles at craft stores (Michael's, HL, JAF) or art supply stores. I've found a limited supply of the InkTense pencils at HL, but mostly I get mine from Dick Blick. You can order multipacks or just a single pencil in a single color. They also make InkTense blocks (look like pastels or charcoals) that you can get slightly wet & "paint" onto the fabric. That makes for a lovely watercolor effect.