Colour Fastness and Sublimation Printing on Polyester Sportswear Fabrics

All-over printed sportswear – from cycling jerseys to patterned leggings – relies almost entirely on dye sublimation. The process produces prints with no hand feel, no cracking and excellent wash durability, provided the fabric and the printing parameters are matched to each other.

How sublimation works

Designs are printed onto transfer paper with disperse inks. Under heat and pressure the ink turns to gas and penetrates the polyester fibre, where it cools and becomes trapped inside the polymer. Because the colour is inside the fibre rather than on top of it, the print does not stiffen the fabric and resists abrasion.

Fabric requirements

• Fibre – polyester above 85% content; natural fibres cannot be sublimated.
• Weight – 190–280 GSM for leggings prints, 130–200 GSM for jerseys.
• Elastane – up to about 20% is workable, but higher content needs lower transfer temperature and longer dwell time.
• Surface – a smooth, tightly knitted face prints more sharply than a textured or brushed face.

Typical parameters

• Temperature: 190–205 °C for polyester/spandex, 205–215 °C for pure polyester.
• Dwell time: 25–45 seconds.
• Pressure: 3–4 kg/cm² on a rotary or flat press.
• Post-print heat setting to fix dimensions and reduce shrinkage.

Common faults and causes

• Ghosting or faint print – temperature too low, pressure uneven or moisture in the fabric.
• Colour shift – ink and fabric batch variation; always approve a strike-off on the production fabric.
• Yellowing or scorching – excessive temperature, especially on spandex blends.
• Edge bleeding – insufficient paper size or creeping during transfer.
• Poor fastness to perspiration – insufficient fixation; verify with alkaline perspiration testing.

Fastness targets

For sportswear, request a minimum of grade 4 for washing and perspiration, grade 4 or better for rubbing, and grade 4 for light fastness where the garment is used outdoors. Always test the printed panel, not the plain fabric, because ink absorption changes fastness behaviour.

Printing is a controlled thermal process. Recording and repeating exact parameters across production runs is what keeps the tenth thousand piece looking like the strike-off.