Partially Oriented Yarn (POY): Specifications, Texturing and Sourcing Guide

A texturing mill that receives 150D/48F partially oriented yarn with elongation at break below 110% will spend the week chasing fuzz and broken filaments, however carefully the machine is set. That is why POY is bought on specification rather than on price alone. POY is the first saleable form of polyester filament: it leaves the spinning line with just enough molecular orientation to be wound, packed and shipped, and it is designed to be drawn and textured downstream, not knitted as it arrives.

Everything else about POY follows from that position in the production chain: low crystallinity, high residual elongation, a narrow and sensitive drawing window, and quality disputes that trace back to the spinning and winding line far more often than to the texturing floor.

What Partially Oriented Yarn Really Is

POY is made by melt-spinning polyester chips and winding the filament bundle at take-up speeds of roughly 2,500 to 4,000 m/min. At those speeds the polymer chains align partway along the fibre axis. That partial alignment is enough for the yarn to hold its shape on a package, but well short of full drawing. Standard textile POY typically shows tenacity of about 2.0 to 2.8 cN/dtex, elongation at break of 100% to 150%, and boiling-water shrinkage of 50% to 70%.

Where "partial" comes from

Birefringence, the optical measure of chain alignment, generally falls between 0.02 and 0.06 in textile POY. That is the practical dividing line between POY and FDY. FDY is spun and drawn in one integrated step at higher speeds and arrives fully oriented, ready for knitting or weaving; POY must be drawn at a ratio of roughly 1.5 to 2.2 before its strength and elongation become useful in fabric.

Package and finish details

Texturing-grade POY carries spin finish at 0.3% to 0.6% oil-on-yarn and is wound into packages of about 8 to 15 kg on paper or plastic tubes. These numbers look minor until a package with uneven density sloughs during unwinding and stops a texturing position.

From POY to DTY: What Happens on the Texturing Line

Most textile POY goes into false-twist texturing. The yarn passes through a heater at roughly 180 to 220 C, takes twist, cools, and is untwisted again, turning a smooth filament into a bulky, stretchy DTY at speeds of about 600 to 1,000 m/min. The commercial point is that the POY specification and the texturing settings are a matched pair: draw ratio, heater temperature and the ratio between the draw and twist zones all have to be tuned to the elongation the spinner delivered.

• False-twist texturing: POY to DTY for apparel, home textiles and sportswear
• Draw winding and draw twisting: POY to a fully drawn flat yarn for weaving and narrow fabrics
• Air-jet texturing and intermingling: POY to air-textured yarns for decorative and technical uses

Because the draw step absorbs most of the elongation, a lot with high elongation variance forces the mill to run below its optimum draw ratio. The symptom is uneven dye uptake and shade banding that only appears after dyeing, which is the most expensive place to find it.

Modified polymers follow the same route on a different chemistry. ECDP pre-oriented yarn is spun from a copolymer that accepts cationic dyes, so the texturing line turns out a yarn that can be dyed in deep shades at lower temperatures without carriers.

ECDP Pre-Oriented POY Yarn for Deep-Dye TexturingModified polyester POY with cationic-dye chemistry, intended for downstream draw-texturing or draw-winding and atmospheric deep dyeing at 85°C.View Product →

POY, FDY and DTY Side by Side

The three names describe stages rather than competing products. The table below collects the values most often quoted in purchase specifications.

If a supplier quotes FDY-level tenacity on a POY datasheet, ask which test method produced the figure. Tensile values are meaningless without the gauge length and testing speed; ISO 2062 and ASTM D2256 are the usual references, and they do not report identical results.

The Specification Sheet: Numbers to Fix Before Ordering

POY contracts that survive a full year of production usually pin down seven items.

1. Linear density and filament count: 75D/36F, 100D/48F, 150D/48F and 300D/96F are common texturing feedstocks, with denier per filament generally between about 1.5 and 4.
2. Elongation at break with a coefficient of variation limit, often 3% to 5% within a lot, which is the single best predictor of texturing stability.
3. Oil pick-up, typically 0.3% to 0.6% for texturing grades, with a stated tolerance such as plus or minus 0.05%.
4. Chip intrinsic viscosity and its lot-to-lot range, because an IV shift changes draw behaviour even when denier and elongation look normal.
5. Package format: weight, tube type, winding tension and a written limit on ribbon build.
6. Defect limits: broken filaments per million metres, slubs, and whether intermingled POY is required.
7. Commercial terms: minimum order quantity, loading port, lead time, and whether test reports are issued per lot or per shipment.

Two of these deserve extra attention. Elongation CV is where a cheap quotation usually hides its cost, and oil pick-up drifts quietly when a metering pump ages.

Where POY Quality Problems Actually Start

Most complaints land on the spinner, and for good reason: the spinning line sets the ceiling on what texturing can achieve.

Broken filaments and fuzz

Filter pressure rise, uneven quenching air, spin-finish starvation at the metering pump and worn guides all produce the same symptom. Once broken filaments reach the heater, they wrap and the position stops.

Denier and shrinkage drift

Pump wear, chip moisture variation and quenching temperature changes shift the draw response gradually. A mill that only checks denier may not notice until a dyed lot shows streaks.

Package formation

Ribbon build, bulging edges and hard shoulders cause tension spikes during unwinding. At fine denier per filament, around 1 dpf and below, the margins shrink further, which is why microfiber grades are ordered with tighter elongation and oil pick-up limits.

Polyester Micro Filament DTY Yarn for Fine FabricsCustom fine-denier DTY with DPF below 0.5, offering soft hand-feel and stable rewinding for lightweight apparel and dense cover fabrics.View Product →

Functional Variants Built on the Same Platform

Standard POY is a commodity; most of the technical interest appears when the polymer or the cross-section changes.

• ECDP and cationic-dyeable POY: a copolymer modification that accepts cationic dye in deep shades at lower temperatures without carriers, with better moisture regain and a softer handle.
• Bicomponent POY: PE/PET or PE/PP precursor yarns textured into bonding yarns where the low-melting sheath fuses during heat treatment.
• Low-melting yarns: sheath-core polyester with a 110 C or 85 C melting sheath, used for shoe uppers and other thermal bonding work.
• Biodegradable routes: PLA filament and staple options for compostable nonwovens and single-use textiles.
• Anti-static grades: modified filament for protective clothing and clean-room fabrics.

These variants are still POY at the point of sale and still get drawn and textured downstream, but the drawing window is narrower and the dyeing behaviour differs enough that the texturing recipe has to be rebuilt from scratch.

Custom ECDP Draw Texturing Yarn for Atmospheric Deep DyeingModified polyester DTY designed for 85°C atmospheric-pressure deep dyeing, suitable for spandex blends and applications from underwear to sportswear.View Product →

Ordering POY from a Spinning Mill: What to Confirm

A trial of 5 to 10 kg per specification tells you how the yarn behaves on your machine. It does not tell you whether the mill can repeat that result twelve months later, so a few checks belong in the first conversation.

• Ask for lot-level tensile, denier, shrinkage and oil pick-up data rather than a generic certificate of analysis.
• Confirm who controls the polymer and the spin finish, since intrinsic viscosity and finish formulation travel with the spinning line.
• Check the container plan: a 20-foot container of POY typically loads around 15 to 20 tonnes, and the pallet or carton layout has to match your tube handling.
• Confirm the loading port. Mills in Jiangsu sit within trucking distance of Ningbo and Shanghai, which keeps ocean schedules predictable for buyers in Southeast Asia, Europe and the Americas.

If you are still separating the stages in your own head, this plain-language explanation of what POY yarn is covers the same ground from the spinning angle. When your denier and elongation targets are fixed, send the specification to our team and we will match it against a production lot.

Partially oriented yarn rewards buyers who treat it as an engineered intermediate rather than a commodity reel. Fix the denier, the elongation CV, the oil pick-up and the package format; verify the data lot by lot; then let the texturing recipe follow the yarn instead of fighting it. That sequence is what keeps shade banding off the dyehouse floor and keeps a texturing position running at full speed.