The scientific definition of sublimation is pretty boring: "the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase." So we've decided to use our own definition of sublimation as it pertains to customizing garments, gift items, and lots of other great products: Sublimation is printing a transfer with your sublimation system, then heat pressing that transfer onto something for a permanent customization with photo-quality images in full, vivid color.
Your sublimation printer uses a special ink that turns into a gas dye when it’s heated up. Ideally, this heat source would be a quality heat press. This hot gas dye is then pressed into the surface of your specialized item, referred to as a substrate or sublimation blank. What’s great about this process is that you’re dyeing the surface of your substrate, so the customization is permanent! Sublimation transfers are some of the longest-lasting transfers out there. For example, coffee mugs are completely dishwasher-safe and will often have the transfer outlast the mug itself.
In order to work with sublimation, your substrates must be specially coated with a thin poly-film in order to react with the dye properly. Some items are made with “poly” materials, like shirts made from polyester (polyethylene terephthalate) or certain plastics made from PVC (polyvinyl chloride). Glitter HTV has certain “poly” properties that allow it to be sublimated. Natural products like cotton are not good at holding onto the sublimation dye, so you can’t use cotton or cotton blends with low poly content. Likewise, untreated mugs like those you find at the dollar tree are not able to be sublimated. In general, you should use items that are specifically marketed as “sublimation”. This ensures you don’t waste money on blanks that can’t be customized.
“Do I really need a heat press?” is a very common question we get and the answer is YES, with one exception: oven wraps. Here’s why: one of the biggest keys to a perfect transfer is even pressure and heat application. If you’re using an iron, this is virtually impossible. With a heat press, you are able to apply even, consistent pressure and heat application. Typically, we recommend using a swing-away heat press for sublimation. The vertical movement of the heating element makes pressing thick, rigid items easier and provides a more even distribution of pressure. This is especially true with items 3/8"-1/2" or thicker. However, a clamshell-style heat press will work perfectly fine for nearly everything else.
Oven wraps are able to do this with curved substrates like coffee mugs, pet bowls, etc. This allows you to skip the heat press and put your substrate in the oven. The tension from the silicone wrap will provide the pressure needed to force the gas dye into the surface of the substrate. You can fit most mugs inside a countertop toaster oven.
*HPN recommends using a dedicated oven for sublimation. Do not sublimate items an oven that is used to prepare food.
So now that we know what sublimation IS, it's time to learn about what you need to get started with sublimation for your hobby, small business, or custom gift enterprise! Check out this incredible video on our YouTube channel. Be sure to subscribe for the latest and greatest sublimation content from the #1 Heat Press Retailer in the USA (that's us, by the way).