Sublimated or heat-pressed: what a number on a jersey actually does.

MORSA RACEWEAR is a Dutch motocross gear brand that makes jersey and pants sets to order, with the rider's name and number sublimated into the fabric. Riders ask us why that one word, sublimated, matters. Here is the plain version.

What is sublimation?

Sublimation is a printing method where solid dye is heated until it turns into a gas and moves straight into the fibre it is pressed against. Epson describes it as a process that "turns ink into gas and embeds it into coated surfaces like polyester fabric". When the fabric cools, the dye is locked inside the fibre. There is no layer on top. The colour is the fibre.

Two things follow. First, it only works on polyester or polymer-coated surfaces, which is one reason race jerseys are polyester (Epson). Second, the garment is permanently dyed, so it "can be washed without damaging the quality of the image" (Wikipedia).

What is a heat-pressed number?

A heat-pressed number is a cut piece of heat transfer vinyl: a plastic film of polyurethane or PVC with a heat-activated adhesive, pressed onto the garment with a heat press (Wikipedia). The number sits on the fabric, not in it. Run a fingernail over it and you find the edge. Film makers publish their own care rules for it: Stahls says to machine wash inside-out with mild detergent and no bleach.

What happens in the wash?

Sublimated: nothing. The dye is inside the fibre, so the fibre has to wear out before the print does. Under normal conditions sublimated prints "will not crack, fade or peel" (Wikipedia).

Heat-pressed: the glue line is the weak point. Every wash cycle soaks, heats and flexes the bond between film and fabric. That is why film makers tell you to turn the garment inside out. After enough cycles the film starts to craze and the edges lift. We print hundreds of names; we do not want to replace them one wash at a time.

What happens in a crash?

A slide on hard pack drags the jersey across dirt, rocks and the bike. A film on top has a raised edge, and the edge is what catches. Once one corner lifts, the number peels from there. A sublimated number has no edge, because there is nothing on top. The fabric can scuff and the colour scuffs with it, but it does not lift or flake.

Does it change weight and feel?

A film adds a layer in the place you move most, across your back and chest. It does not stretch the way the fabric stretches, it holds heat, and you feel it when you are soaked in sweat. A sublimated number adds no layer: the finished print is "smooth to the touch" (Epson). Your name weighs nothing.

Why does MORSA sublimate the Rider ID?

Because your name and number go into the print file before the fabric is printed. They are printed in the same pass as the design, so they cannot be added badly, applied crooked or peel later. The Rider ID is included on every set, adult and youth, at no extra cost: a name of up to 14 characters and a number of up to 3 digits. You confirm the spelling twice at checkout, and you can change it free until your run closes on Friday at 12:00 Amsterdam time.

How should I wash a sublimated set?

Wash it the same day it comes off the bike, at 30°C with normal detergent, pants inside out. Hang it to dry. No tumble dryer, no bleach, no fabric softener, and do not iron the print. Mud left to dry grinds into the fibre, so the same-day rule is the one that matters most. Do that and the print lasts as long as the jersey.

Questions about the Rider ID? The FAQ covers limits, checking and changes.