Heat Transfer is a 2-step process:
- Print a design onto a transparent sheet of transfer paper/film (DTF Pretreat Sheet).
- Add adhesive powder (DTF Pretreat Powder) on the image that was printed onto the transfer paper/film, melt it down using a heating element and subsequently heat press the transfer paper on the substrate.
Cold-peel the transfer paper off the substrate and you will have the design transferred onto the substrate.
Note that a different feel will exist on the substrate along the area where the image is placed, as it is imprinted onto it. (Powder and ink form an extra layer)
Sublimation Printing:
You print the image onto a regular copy paper or specialty sublimation paper and then use a heat press to transfer the image into the substrate.
The difference in how these two printing methods work lies in the science behind Sublimation:
Sublimation employs toner ink which turns from a solid to a gas state during transfer (when heated). It reaches the substrate in a gas state and penetrates it. When it cools down it reverts back to a solid state which is by then part of the substrate itself (no extra layer / different feel).
Differences in durability:
Heat transferred images will last about 30-40 washes depending on the size of the design and how it is being washed.
During Sublimation, ink toner is infused into the substrate. More than 100 washes will be needed for the image to start fading away, which is likely to be the life of the substrate/garment itself (no cracks-the image is into/part of the fabric).
Differences in Variety:
Sublimation: The variety of substrates into which you can transfer your image is limited as compared to Heat Transfer. The substrate material must constitute mainly by polyester. The more the polyester % in the blend, the more vibrant the colors.
Polyester 60% - Cotton 40% would have much less vibrancy than 100% polyester (best quality/print color vibrancy). Less than 60% polyester present in the blend is not recommended.
Moreover, the color of the substrate can only be white or any very light color. With Sublimation, the ink will not show on a darker substrate.
Heat Transfer:
The substrate can be of any color. It can be polyester/cotton based and any blend % between them. The substrate material can also be ceramic, would, or metal.
What about Color Quality?
Sublimation:
Allows combinations of 4 colors so it can reproduce/sublimate high quality photos, custom logo prints etc.
Heat Transfer:
Heat Transfer paper/film can also create very vibrant and sharp quality designs employing 4 color-combinations.
The differences between the two printing techniques lay in feel, durability and the variety of the substrates that they can be applied in.