DTY vs FDY vs POY: Polyester Yarn Types Explained
POY, FDY and DTY are three forms of polyester filament yarn. They come from the same melt-spinning process but are finished differently. Knowing the difference helps when you specify a yarn — or read a grey melange spec like “combined DTY/FDY”.
POY — Partially Oriented Yarn
POY is polyester filament that has been only partially drawn as it is spun. It is not usually a finished fabric yarn; it is the feedstock that gets further processed — drawn into FDY or draw-textured into DTY. Think of it as the intermediate stage.
FDY — Fully Drawn Yarn
FDY is fully drawn and oriented in a single step, producing a smooth, flat, lustrous filament with high, even tenacity. It is used where a clean, strong, slightly shiny filament is wanted — linings, silky wovens and smooth knits.
DTY — Draw Textured Yarn
DTY is POY that has been drawn and textured (crimped and heat-set) at the same time, giving the filament bulk, stretch and a softer, more matte hand. It is the workhorse of knit apparel — single jersey, fleece, activewear and socks — wherever softness and stretch matter.
Side by side
| Property | POY | FDY | DTY |
|---|---|---|---|
| Finishing | Partially drawn | Fully drawn | Drawn + textured |
| Look | Intermediate | Smooth, lustrous | Matte, textured |
| Hand | Feedstock | Crisp, flat | Soft, bulky, stretchy |
| Typical use | Feedstock for FDY/DTY | Wovens, linings, smooth knits | Knit apparel, activewear, socks |
How this applies to grey melange yarn
A grey melange filament yarn gets both its look and its hand from which filaments are combined. Pairing a textured DTY (matte, bulky) with a smooth FDY (lustrous) — or combining two DTY ends — changes the surface and feel of the finished fabric. That is why we set the construction (DTY/FDY or DTY/DTY) to match the fabric you are making.
See what grey melange yarn is for the heather-grey basics, or go straight to our grey melange polyester yarn specs and request a sample.