Mugs are created through a process called dye sublimation. A transfer paper is printed with ink that will release from the paper under the right amount of heat and pressure.
Mug artwork is inkjet printed, using special dye-sublimation inks and transfer paper. After printing, the transfer paper is wrapped around the mug. The image on the transfer paper is mirrored. Heat and pressure is applied to transfer the image. Printed dye is mixed with the coating. The image then becomes part of the mug.