Cationic (Cationic-Dyeable Polyester)

Cationic polyester is a modified polyester that accepts cationic (basic) dyes. Regular polyester has no affinity for them and is dyed with disperse dyes instead; the cationic variant is built with dye sites that a basic dye bonds to directly. The practical result is deeper, more vivid colour at a lower dye load, and the two-tone effects buyers ask for by name.

How cationic fabric is woven on waterjet looms

Cationic fabrics achieve their heathered, two-tone appearance on the loom rather than in the yarn-dye house. The mill places Cationic Dyeable Polyester (CDP) in either or both yarn directions, paired with regular PET, and the dyehouse delivers the contrast in a single bath:

• Warp-dominant CDP (most common): CDP yarn (e.g. DTY 100D/36F) on the warp beam; regular PET DTY (e.g. 100D/36F) on the weft insertion. The dominant warp covers more of the face, so the CDP color reads on the surface.
• Weft-dominant CDP: Regular PET warp with CDP weft for the inverse effect — useful when the design brief calls for a cooler surface color with CDP shadow showing only on the back.
• Bidirectional (50/50) CDP/PET: Both warp and weft blend CDP and PET — produces a true melange with no directional bias, common in heathered upholstery.

During jet dyeing, a one-bath two-dye system is used:

1. Cationic (basic) dyes bond to the modified CDP fibers due to the anionic sulfonate groups embedded in the polymer chain.
2. Disperse dyes color the regular polyester fibers.

By adjusting the dye concentrations in a single cycle, mills produce contrasting shades (e.g., charcoal and light grey, or navy and sky blue) without the high minimums and lead times of cone-dyed yarn weaving.

Why it dyes differently

The fibre is copolymerised so it carries dye sites a basic dye can attach to. That changes three things on a purchase order:

• Colour depth — richer, more saturated shades than the same shade on regular polyester
• Dye class — it is dyed with cationic (basic) dyes, not disperse
• Cost — a cationic fibre usually carries a premium over standard polyester

The two-tone effect

Blend cationic and regular polyester in one yarn or fabric, dye once, and the two take the dye differently — one deep, one pale. That single-bath contrast is the "cationic" look: a heathered or two-tone surface without a second dye run.

Where it is used

• Apparel and sportswear — deep shades and two-tone knits and wovens
• Home textiles — decorative two-tone effects where a colour contrast is wanted in one cloth
• Blends — wherever a one-bath contrast is cheaper than two dye lots

What to put on the RFQ

• Fibre — state "cationic-dyeable" explicitly, not just "polyester"
• Colour and depth — the target shade, since cationic shifts depth
• Construction — woven or knit, weight in GSM, and width
• Dye route — cationic vs disperse, and whether a two-tone effect is intended

We are a woven polyester mill; the base cloth is our part, and the fibre specification drives the colour. Start from greige fabric or request a quote.