Dye migration on polyester happens when cure or press heat turns the dye in a polyester garment into a gas that moves into the print above it, so the fix is less heat on the garment plus a low bleed ink or blocker layer, confirmed by testing the blank first.

Definition: dye migration

Dye migration (also called dye bleed) is when dye in a polyester or poly blend garment turns to gas under heat and tints the print above it, often turning white or light ink pink, gray or green.

Part of the DAX Learning Hub: practical, exhibitor neutral guides for apparel decorating. If a transfer is lifting rather than changing color, see Heat Transfers Not Sticking.

Published by DAX (Decorated Apparel Expo) · Last updated: October 2026

Find more screen printing guides in the DAX Learning Hub. Related guides: Screen Printing for Beginners: Process, Equipment, and When It Pays Off and Plastisol vs Water Based Ink: Differences, Curing, and When to Use Each.

What Is Dye Migration?

Polyester is usually colored with disperse dyes, the same family of dyes used in sublimation. They are set into the fiber with heat, which means enough heat later can release them again. Published ink and garment technical bulletins commonly put the point where some disperse dyes start to move at roughly 265°F (about 130°C), well below many standard plastisol cure temperatures.

The result shows up in the lightest colors first: a white underbase or a pale spot color picks up a tint from the garment underneath. Dark and bright polyester, tri-blends and sublimated patterns are the usual suspects. Cotton and nylon garments carry a much lower risk.

Why Polyester Bleeds Into Prints

• Too much total heat. Every flash, the dryer and any post press add heat. Many flashes on a multicolor job can trigger bleed even when the dryer setting looks fine.
• Ink not built for polyester. Standard cure inks need more heat than many dyed polyesters tolerate.
• Hot stacking. Garments stacked while still hot keep cooking and can bleed into each other or into the print.
• Dye lot and color. The specific dye, garment color and dyeing process all change how easily a blank bleeds, so two similar looking shirts can behave differently.

How to Prevent Dye Migration

1. Know the blank. Check fiber content and color before you quote. Polyester, blends, tri-blends and sublimated patterns need the polyester process.
2. Choose a low cure or low bleed ink. Low cure inks are typically formulated to cure somewhere in the range of about 260°F to 300°F (about 127°C to 149°C), depending on the product. Follow your ink spec.
3. Add a blocker when needed. A gray or black bleed blocker underbase absorbs migrating dye before it reaches the top colors. Low bleed whites resist bleed but are not always strong enough for heavy bleeders.
4. Cut total heat. Flash only to the gel point, avoid extra flashes, and run the dryer at the ink spec rather than above it. For dryer roles, see Flash vs Conveyor Dryer.
5. Still cure fully. Lower heat is not permission to undercure. Check cure with a stretch and wash test. For the full cure process, see How to Cure Plastisol Ink.
6. Cool before stacking. Let garments cool before they are stacked or boxed.

How to Test a Garment for Bleed

Print a white or light test block on a sample of the exact blank and dye lot, run it through your normal flash and cure, and let it cool. Compare it with an unprinted area and with the same ink on a non bleeding garment. Check again after a day or two, because some migration shows up hours or days later rather than at the end of the dryer. If you see a tint, step up to a low cure ink, a blocker, or both, and test again.

Dye Migration in DTF and Heat Transfers

Dye migration is not only a screen printing problem. Heat applied transfers, including DTF, can show bleed when press heat reactivates dye in a polyester garment. Common controls are a lower temperature transfer or adhesive designed for polyester, a dye blocking adhesive or blocker layer where offered, and a test press on the exact blank. Follow your film or transfer supplier spec for temperature and time. Typical published figures for DTF on performance polyester sit around 270 to 290°F, and many heat transfers rated for polyester apply below about 300°F. Always follow the product spec and test first. For press settings on performance fabrics, see How to Heat Press Performance Wear Without Scorching or Bleeding. For wash failures that look like cracking or lifting rather than color change, see DTF Transfers Cracking or Peeling After Wash.

Frequently Asked Questions About Dye Migration (FAQ)

What causes dye migration?

Heat. Disperse dyes in polyester can turn to gas and move into the ink or transfer when the garment gets hot enough, often starting around 265°F (about 130°C) for sensitive dyes. Many flashes, a hot dryer and hot stacking all add to it.

Does low cure ink stop dye migration?

It reduces the risk a lot because it cures at lower temperatures, often about 260°F to 300°F depending on the ink. Heavy bleeders may still need a blocker underbase. Test the blank and follow your ink spec.

Can dye migration happen days later?

Yes. Bleed can appear hours or days after printing or pressing, especially if garments were stacked hot. That is why a test print should be checked again after a day or two, not only at the end of the dryer.

Does DTF have dye migration?

It can. Press heat can pull dye from a polyester garment into a DTF transfer. Lower temperature or dye blocking adhesives and a test press on the exact blank reduce the risk; follow your film or transfer supplier spec.

Temperatures and ranges here are typical published figures. Follow your ink, film or supplier spec for every garment and product.

Testing one garment before a run is the cheapest insurance against bleed. Browse more guides in the DAX Learning Hub, and check cities and dates on the DAX show schedule to compare low bleed inks, blockers and transfer options with suppliers in person.