What Is Dye Migration and How to Prevent ItBy Shirtspace | Nov 08, 2017 | Updated Oct 23, 2020
Whether you’re new to screenprinting or have been in the industry for years, it’s a good idea to familiarize yourself with dye migration. Learning what it is and how to prevent it will save you botched jobs and future headaches.
Dye migration occurs when dye from polyester fabric bleeds into the ink that is screenprinted on the garment. An example of this is white ink that turns pink after having been printed on a red polyester t-shirt.
What causes dye migration?
Curing ink requires using heat. The problem at hand is that both plastisol and water based inks must be cured at 320-330 degrees to prevent the ink from washing out when laundered, but when polyester fibers reach 280 degrees the dye from the fabric can begin to bleed into the ink. What’s worse, is that dye migration can occur several days after printing so it won’t immediately be visible.
How do you prevent it?
1. Print with specially formulated dye blocking polyester inks or low cure inks
Ink manufacturers are well aware of dye migration and have formulated inks that are specifically designed to print on polyester fabric. Some of these inks cure at a lower temperature so that you don’t have to worry about reaching 320 degrees, while others are formulated using dye blocking characteristics and cure at the standard 320 degree mark. Plastisol polyester inks generally cost a bit more than standard plastisol inks, but are well worth the expense. At this time we aren’t aware of waterbased polyester inks, but hopefully they’re on the horizon!
2. Use low cure additive
Low cure additive is used to reduce the curing temperature of both plastisol and waterbased inks. You simply add your additive to your ink based on the manufacturer’s instructions, mix it up, and print.
3. Print a white underbase
For those that are new to the game, a white underbase is when a white layer of ink is screenprinted, flash cured with a flash dryer or heat gun, and another layer of color ink is printed on top. Printing a white underbase on dark garments is a widely used screenprinting technique that’s a great way to achieve bright colors, and when printing on polyester garments, can prevent dreaded dye migration.
Printing a white underbase using dye blocking polyester ink that cures at 320 degrees allows you to print your base, flash cure, and print standard plastisol ink on top.
Printing a white underbase using low cure ink is another great option, but you must also print low cure plastisol on top of it so that the cure temperatures are the same.
Finally, one last parting thought on dye migration.
If you’re printing plastisol ink that is darker than the garment you’re printing on (example: black ink on white shirt, navy ink on grey hoodie) you can skip the special polyester inks and additives. While the dye from these garments may technically bleed into the ink, the darker ink prevents the dye migration from being visible.
Ok, one last parting thought :)
As with anything, the fail-safe way to know that your screenprinting process has gone smoothly is to TEST, TEST, TEST. Testing generally involves using one of the suggested methods above, printing your garments, waiting 72+ hours, and watching for dye migration. Though this takes extra time and is admittedly inconvenient, testing is the only way to definitively know that nothing has gone awry.
Good luck and happy printing!