Review on Sakura Pigma 30063 Micron Assorted Colors Ink Pen Set - 01 Tip, 6CT Blister Card by Tammy Pochmara

I used to love these pens and had a pair from my college days over 12 years ago and they still worked. I used it on a surface painted with matte acrylic paint and half seemed to dry leading me to believe that fine particles of paint had somehow clogged the tip and the ink stopped flowing. So I ordered this set of pens along with a pack of black in different widths only to find these new ones also dry up then go back to full ink flow then after a minute the lines go invisible and so on and this happens when I use them on regular printer/copier paper and a sketchbook. It doesn't always happen to everyone, but I've noticed it with black and brown - these two regularly dry out for a second until I scribble some quick lines on a piece of paper, they come to life and then fade away again pretty soon.