This is a piece of fine grit sandpaper. It's not perfect, but at the time it's all I could come up with.
I may try it again, but with some experimentation. Perhaps take a wire brush, and smack the sandpaper on the backside to give it some texture? It may work, or not.
I like the dryer sheet idea. I also would try a dark grey flock material.
It's threads like this that make this board so valuable.