Tip 1 (Pre-Shrinking): Heat Presses operate at incredibly high temperatures, which is necessary for the sublimation process to take place. Some polyester can react to this heat and it can cause it to shrink by up to 10% when it goes through the press. As a result of shrinkage you may find that some ‘ghosting’ appears on your fabric and designs are not as crisp as they should be. To avoid shrinkage always test your polyesters first by measuring a piece, putting it through the press, and measuring it again to see if it’s changed size. If it has changed size then you may need to put the material through the press before printing on it, essentially ‘pre-shrinking’ the fabric.
Tip 2 (Double Sublimation): Because we can never transfer 100% of the ink from the sublimation paper to the substrate, there is a risk of ‘Double Sublimating’ products if care is not taken when removing items from the heat press. When using a rotary heat press it is important to separate the textile and waste paper as they come off the drum, as the residual heat can cause sublimation to continue and you will end up with a blurry or ghosted image. When using a flatbed, unless the paper is held in situ with heatproof tape, it is best to remove it as soon as possible.