Dye Sublimation (or dye-sub, for short) is a common way of printing on various fabrics, and is used by printing companies around the world as a quicker and more cost effective alternative to screen printing on fabric. The design of your fabric banner is printed in reverse on a heat transfer paper. Once it is printed, both the paper and the polyester fabric go through a heat transfer machine that acts like a large iron, transferring the image from the paper directly to the fabric. This actually dyes the design into the fabric creating a durable high-quality look that can also be easily cleaned.