My friend and I have been testing my new Frixion pen this morning. The package says if the pens get too hot, cool them down to make color reappear. I knew that ironing caused the color to disappear, but if I put my quilt in the car and it gets down to zero, will all my lines reappear????
Well, so far, that is what has happened.
1. We tried putting the sample in the freezer after we had ironed the color out, and it all came back clear as could be.
2. We tried washing it in clear water, drying then freezing and again the lines reappeared totally.
3. The last test, I scrubbed the piece with detergent, rinsed, dried and froze--those lines did NOT reappear.
CONCLUSION: if you really want to be sure the marking lines are gone, you had better wash your quilt top with detergent.
Thought this might be of interest. I think the pens are relatively new. The quilt shop owner just showed us how the lines vanished with heat--we were curious about the effect of cold after reading the fine print on the package.