Quote Originally Posted by Lukas Werth View Post
I once tried to print with casein/gum (direct pigment, in this case cobalt oxide) on ceramic tiles which were then glazed over. I was successful of sorts: the result was a blue image with beautiful tonations and shadows, but there were some blisters in the glazing which were difficult to get rid off (not impossible, that is, but I spopped my experiments at that point for other reasons.
Lukas, I'm really interested in your description, since I'm about to try printing gum on some ceramic floor tiles that the previous owner of the house left here. These are glazed, not shiny glazed but smooth and slick enough that I'm going to need to fashion some way of helping the gum adhere. I'm thinking I'll sand the tiles and then use pumice in acrylic to add tooth. Then if I could print gum on that successfully, I was thinking of using some sort of sealer on them. I'm not clear from your description; were these unglazed tiles that you printed on and then glazed and fired? That would probably be the most reliably durable way of printing on tile.