|A couple months ago I purchased a package of Uni-ball Gel Impact pens as recommended for safe check writing. The experts said the ink in these pens could not be removed in "check washing scams" [stolen checks from mailboxes, rewritten].
I got to thinking, if this ink wouldn't wash out of paper with acetone by scammers, it shouldn't wash out of fabric with detergent. So, I decided to conduct an experiment.
I ironed some freezer paper onto the backside of some plain fabric [for ease in writing], and wrote on it with one of these pens. I ironed over half the writing, or heatset. Then I put the fabric by my washing machine so I could put it through many wash loads to see how it held up.
Good news! The ink is not fading on either side, so heatsetting the ink with an iron isn't even necessary. But also, it doesn't hurt anything if your iron does touch this ink.
These pens write on fabric so much easier than the special permanent fabric pen I bought. A package of 2 costs less than $5 at Walmart.
This is a nice way to make a handwritten label for the back of a quilt, to show who made it, when, where, etc. Fold the edges under to clean finish, while the freezer paper is still attached, for an easier fold. Press, then peel the paper off before sewing onto the project.