The ink reacts poorly with heat. If you leave this notebook anywhere outdoors, in a hot car, storage unit, suitcase, etc, the ink will disappear. I left this notebook in my car, and all of my notes were unreadable the next day. Please be careful buying this if you live in a warm climate.
Hello - we are sorry to hear that your notes disappeared! This can happen because the FriXion ink is heat sensitive so leaving it in a hot car or other extremely hot place can make the ink disappear. However, if you place your notebook in the freezer for a bit, your notes should be visible again. This freezer trick will also work if you leave your pen in a hot place and it stops working!