It can happen that when you’re printing with a low-bleed or bleed-resistant white on dark tees, you can end up with “ghost” images on the back of the garments.
The usual assumption is that the print has somehow penetrated all the way through the tee to the back. Usually that’s not the case at all. What often happens is that the garments are stacked as they emerge from the dryer. Because the dye-block ink film is still hot and therefore the dye-block chemicals are still active, they “bleach” the dye in the back of the shirt stacked on top. The result is a “ghost” image on the back of the shirt on top.
The solution is quite simple and only requires a change in the stacking routine at the end of the dryer. Instead of building a single stack and completing it before starting a new stack, have five or six stacks going at once and stack them in a rotating pattern. In other words, the first garment goes on stack number one, next one on stack number two, next one on stack number three, and so on. By the time you’re back at stack number one the last print should have cooled off enough so as not to “bleach” the back of the next shirt on the stack.
No need to call Ghostbusters.