TSF-06 · Print
Print cracking on jersey: stretch, ink, and cure
Fault: Print cracks & flakes:
Seen as:
Print splits across the fabric’s stretch after a few wears or washes.
Root cause:
Under-cure below fusion temp, brittle ink, or a rigid film on stretchy low-GSM knit.
Fix:
Cure to ~160°C / 320°F, add stretch additive, reduce deposit, and match ink to fabric.
Test:
Wash test + stretch test on a cooled print; verify cure temp with a probe.
A jersey tee stretches. Your print has to stretch with it.
When the ink film can’t move with the fabric, it splits, and that crack is the most visible print failure there is.
Three things cause it:
How the print was cured, what ink was used, and how thick it went down on a stretchy knit.
Under-curing: the number-one cause
Most tee prints use plastisol ink, essentially PVC resin plus a plasticizer.
It doesn’t soak into the fabric; it sits on top and forms a mechanical bond as it fuses.
That fusion matters. Most plastisols fully cure around 320°F (160°C), with working ranges roughly 300-330°F depending on the brand’s data sheet.
Reach that temperature through the whole ink film, and it fuses into a tough, flexible layer. Fall short and it never fully bonds it stays brittle, and it cracks.
FROM THE FLOOR:
Here’s the trap: plastisol gels become dry to the touch at around 230°F (110°C), long before they’re actually cured.
So a print can feel finished while it’s still under-cured.
A dry-to-touch print that never hit fusion temperature is a cracking complaint you’ve already shipped.
The failure chain:
Dyer too cool or belt too fast → film never hits fusion temp → print looks fine, feels dry, and cracks after a few wears and washes.
A thick deposit hides it; the surface cures while the underside never reaches temperature.
Cheap, low-elasticity ink:
Budget inks skimp on the plasticizer that lets the film flex.
Even fully cured, they crack because the film itself can’t stretch.
This is a formulation problem, not a cure problem; you solve it by buying better ink or adding a stretch additive.
Fabric that outstretches the ink:
A stretchy, lightweight jersey moves more than a stiff ink film can follow.
Lower-GSM fabric stretches most, so it splits prints soonest.
A heavy ink deposit on a thin stretchy tee is a crack in waiting; the fabric goes one way, the rigid film can’t, and it fractures.
High-heat home laundering:
Repeated hot drying makes PVC brittle over time.
You can’t control the customer’s dryer, but you can build the print to survive it proper cure and a flexible ink gives you the margin.
Prove the cure: don’t hope
Two tests catch a bad cure before it ships.
The wash test is the definitive one: wash the printed tee hot with strong detergent; a properly cured print survives repeated washes, and a badly under-cured one shows damage within one to three.
The stretch test is fast and daily; stretch the print to about two-thirds of the fabric’s stretch; if it cracks and doesn’t spring back, it’s under-cured.
One catch: let the print cool fully first. Warm plastisol stretches fine and gives a false pass.
Wait for room temperature, or you’re fooling yourself.
Back both up by measuring dryer temperature directly with a temperature gun or thermal probe on the ink, not by trusting the dryer’s dial.
Printing on a hoodie rather than a tee? The fabric is heavier, and the cure behaves differently. See our companion guide on how to stop screen prints from cracking on hoodies.
For the full comparison of print methods plastisol, water-based, and discharge, and where each belongs, see our guide to t-shirt decoration methods.