Dye turns to gas under heat and bonds into polyester or a coated surface, so the image ends up in the material rather than sitting on top of it. Nothing to peel, nothing to crack, and it is the only way to get genuine edge-to-edge color on a desk mat, a table throw or a tumbler. It needs polyester or a poly-coated blank — it will not take on cotton — and white is the only base that behaves like a blank canvas.