ImagesMagUK_September_2020 28 images SEPTEMBER 2020 TIPS & TECHNIQUES Simon Lymn, machinery sales manager at I-Sub, provides an essential guide to dye sublimation transfer paper technique from ‘surface-covering’ techniques (such as screen printing plastisol ink). There are many different types of dye sublimation paper: barrier papers, high-release paper, microporous paper, thermal adhesive or TA/Tacky, coated, lightly coated and non-coated. Breaking them down To make sense of these different terms, it helps to understand two important aspects of the paper: its structure, and whether it is coated or not coated. The paper structure (which includes gsm, ie grams per square metre) can determine the way in which the paper reacts in general. This may only be truly evident upon testing, but the supplier should have a good idea. Some papers are ‘barrier’ papers, which means they are essentially non-porous, and so during the sublimation pressing the dye sublimation gasses will not travel though the paper very much. Other papers are microporous, which means that the gasses are able to travel through the paper during pressing. This is a benefit when printing onto very wide format, or rigid or non-porous media (such as metals, ceramics, glass or coated textiles). Porous papers help prevent the bubbling or ‘rivering’ effect that can occur when the gasses are not able to escape during the heat pressing – a common complaint when using barrier papers on non-porous media. The equipment you use and your workflow will also have an effect on paper choice. For example, with ceramic mug printing, quick-dry barrier coat papers are actually more suitable as they enable quick ink drying between printing and pressing, and prevent the dye gasses moving through the paper during the pressing and staining the mug-wrap mechanism. Coating options The second aspect to understand is the coating. Coated/not-coated is literally that – has the paper been coated? There are numerous types of coatings which enable the paper to do different jobs. Quick-dry (or instant-dry) coatings allow the ink to dry fast. This can improve how stable it is during printing, and it also helps prevent the ink from rubbing off during winding. High-release coatings transfer a higher percentage of the dye sublimation inks to the substrate, resulting in a better colour yield on the fabrics or objects that are being printed. Simon Lymn Industry experts provide insight and guidance in all areas of digital garment and textile printing Digital helpdesk D ye sublimation transfer paper is a sacrificial paper used to transfer inks to (predominantly) polyester textiles. The paper can be coated or uncoated, and serves as a receptacle for dye sublimation inks. Dye sublimation inks are commonly delivered to the paper via a digital inkjet printer. The printed imagery/designs on the paper are then transferred via heat and pressure into polyester-based textiles and suitably coated objects. They are transferred ‘into’ the textiles rather than ‘onto’, as the inks permanently dye the material on a molecular level. It is this which differentiates the dye sub printing A roll of dye sublimation transfer paper