Curing

Curing is the step where plastisol ink stops being a wet, movable paste and becomes a permanent part of the shirt. It doesn't dry the way paint dries in open air — it has to hit somewhere around 320°F (160°C) for a sustained stretch, usually 60 to 90 seconds at that peak temperature, so the PVC resin and plasticizer fully fuse into a continuous film that's mechanically locked into the fabric's fibers.

For the buyer, curing is invisible on delivery day and everything on wash day ten. A shirt that looks perfect coming off press but was under-cured will crack, flake, or fade within a handful of washes, while a properly cured print on something like a 6.1 oz Gildan Ultra Cotton tee should hold up for years of regular laundering. We've had returns come back where the shirt looked fine but the ink rubbed off on a fingernail — the surest sign of an under-cure.

Shops verify the cure with a peel test, a wash test, or an infrared temp gun run across the print immediately off the dryer, not just by trusting the dial on the conveyor oven. Thicker ink deposits, like a heavy underbase on a dark shirt, need longer dwell time to cure all the way through than a thin single-color hit on a light tee.

The most common misunderstanding is that ink 'looks dry' means it's cured. Plastisol can feel completely set to the touch straight off the dryer belt and still be badly under-cured underneath, because curing and surface dryness are two different things — the surface skins over well before the ink actually reaches full cure.