I bought a package of black pens that I loved. In my last visit to Staples there was a box of red pens on clearance and I bought it for a special project. The box was left over on the shelf for a while and the pens had leaked a bit and the ink had dried out on the tip. I had to scratched hard the pens against the paper but once this was done for each one for a few seconds they worked beautifully.