November/December 2008

Cheat Sheet

 

Dye Sublimation

By Matt Histand

Q: I’m familiar with screen printing, but when I’m asked by clients about dye sublimation I’m at a loss for details. I know sublimated images feel and look different than screen printing, but I don’t know enough about the process to give an educated response. Can you give me the basics on how the process works so the next time a client asks, I have some answers?

A: Dye sublimation isn’t a new process but you’d be surprised by the number of your fellow distributors who have the same question. Let’s put on our lab coats and talk about the sublimation process: It’s the chemical process in which a solid is converted into a gas without first entering the liquid state. Dry ice is the most well-known example of this process. The ice doesn’t melt into a pool of water, but turns directly into a mist-like gas.

So what does all that mean? Unlike screen printing, where color is directly applied to a garment through a screen, dye sublimation works by printing the image on a special paper, usually either bonded or high release (see sidebar, “Four Keys to Dye Sublimation.”) That paper is then placed on top of a garment and run through a heat press at 400 degrees for 30 to 40 seconds. The heat, along with the pressure, turns the ink into a gas, which penetrates the shirt’s fabric. Once the heat is removed, the gas, which contains the ink, solidifies and bonds with the fibers.

“The final product is a fabric that’s dyed and not painted, so to speak,” says Michael Labella, product manager for US Sublimation, a supplier of sublimation equipment. “The color doesn’t sit on the surface of the fibers, but actually inside of them. And because of that, the print is very durable. It doesn’t peel. It doesn’t crack. It doesn’t wash out. As long as the fiber stays intact, the color stays locked into the fabric.”

Dye sublimation is used on 100% polyester garments, because cotton doesn’t sublimate. What makes polyester work is that it contains tiny pores that open up when heat is applied and close again when it’s removed, locking the ink particles left behind after the water from the ink evaporates.

The process can produce garments with strong colors and is great for high-tech, performance fabrics. Because sublimated images don’t peel or crack like screen printing, it’s great for garments that need repeated washings or that will take abuse such as a football or baseball jersey. It’s also very commonly used in fitness apparel and all-over-print bicycle jerseys.

However, there are some drawbacks to using dye sublimation, particularly clarity of the printing, which isn’t as sharp as screen printing, and a slower printing time per garment. Another is the truth about all-over prints. While dye sublimation is often touted as a plus, and can be, it’s best when done before a garment is constructed. Because most garments in this industry are decorated after they’re put together, all-over printing can
create problems.

“Since it’s almost impossible to lay a T-shirt completely flat on a press without any wrinkles, what happens is that around the seams you’re going to notice a slight line of faded color because you can’t apply even pressure,” Labella says. “The same goes for under the armpits or any area you can’t lay flat. There will be some wrinkles and the colors won’t penetrate the wrinkles.”

That said, decorators have learned to turn dye sublimation lemons into lemonade. One of the hottest styles at retail and in promotional apparel is the destroyed look. The way the look is often achieved is by dye sublimating a polyester shirt blended with cotton. The result is that only the polyester fibers hold the ink, creating a shirt that looks worn out from the cotton fibers. The sublimation is also done after the garment is sewn together, which adds fading around the seams and underarms for a perfectly distressed look.

Four Keys to Dye Sublimation 1. The right printer. There are four leading manufacturers that produce printers as well as a handful of others. They range from a desktop model all the way up to a 128-inch-wide format. Do your research to make sure you choose the right model and avoid overspending or upgrading too soon. 2. The right ink. Inks from different companies are different. The colors vary and some contain more water then others requiring you to lay down more ink. Labella recommends you request data findings from each ink company. They contain test results on fading, washing, rubbing and alkalinity (sweat). 3. The right paper. Bonded paper is most common, but only releases about 60% of its color vs. a high-release paper that has a waterproof-like barrier that keep ink in a sort of gel. It releases up to 95%, but is more expensive. 4. The right heat press. Don’t skimp on the heat press, Labella says. It’s the most expensive part of the process and it’s where companies often cut corners. The problem is that even heat produces the best sublimation. Cheaper or older presses can result in variations in temperatures, which can cause the ink to fade in the sun or rub away.

Customize Each Shirt Sublimation uses digital technology that allows a decorator to make changes to each individual shirt if needed. Screen printing on the other hand is done with a series of screens. So if you’re doing jerseys for a sports team that requires individual names and numbers on each jersey, additional screens need to be made for each one. That’s not so with digital technology such as sublimation. In the case of dye sublimation, you can upload a list of names and numbers and print out custom designs for each garment. “The advantage of digital technology is that it allows you to do very short runs with no additional costs and manage the print files in ways that you were otherwise unable,” says Michael Labella, product manager for US Sublimation. “The technology automatically adds customer details, making each garment unique without adding to the cost of the product cycle.”

Matt Histand is an NJ-based contributing writer.