This mug was designed by Steven Frank and printed by Zazzle.
The top part of the design was much darker six months ago. Zazzle’s
process appears to involve shrink-wrapping a layer of plastic over the
mug and then printing on that; you can’t see it in the photo, but the
plastic has started to peel off near the top of the handle. I have
another such mug, printed using a different process in 2003 for the
Stanford Film Society’s “Film Our Way” festival; it didn’t fade
nearly as fast, and there wasn’t any plastic to peel off, but after
seven years of use the design is almost gone.
The problem with these mugs is, the design is printed on top of the
glaze. Truly permanent decorations on ceramic are either done with
the glaze itself, or are inked directly on the unglazed piece and then
covered by transparent glaze. Either way, the decoration happens
before the glaze firing. Unfortunately, glaze kilns are typically
designed to process hundreds of pieces per batch, and take several
days to go through a complete cycle. That’s not practical for a
print-on-demand outfit.
I think you could design a much smaller kiln, with space for just a
few mugs, though. It’d be lined with fiberglass instead of firebrick,
to reduce the thermal mass; since there’s no need for a reduction
phase with clear glazes, it could use electric heat. It’s not
possible to do a stoneware firing in less than about 24 hours start to
finish, because the clay will crack if you heat or cool it too fast
(this is why raku-glaze pieces are often fragile) but there would
be no need for several days’ worth of cooling time as is typical for
large batch kilns.
