Le fil de polyester est un matériau idéal pour le tricotage (tricot trame, tricot chaîne) ou le traitement tissé.

Polyester yarn is suitable for making clothing fabrics (such as suits, shirts), bedding (such as quilt, bedspread, mosquito nets) and decorative articles (such as curtain cloth, sofa, wall cloth, car interior decorative cloth), etc. Fine denier polyester silk yarn (especially three-leaf shaped polyester silk yarn) is more suitable for silk-like yarn fabrics, medium denier silk can be used for wool-like fabrics.

Polyester yarn not only has the characteristics of high breaking strength and modulus of elasticity, excellent heat setting, good resilience, heat resistance, light resistance, corrosion resistance, easy washing and quick drying, but also has the characteristics of high bulkiness, good heat insulation, comfortable handle and soft gloss.

Low elasticity silk polyester yarn also has sewing function, the edge is also known as the lock edge, English became overlocking, all clothing pieces need this process. 

Because the main purpose of edge-folding is to keep the polyester yarn from falling off, the requirement for the strength of edge-folding yarn is not high. In order to save cost, the edge-twisting yarn is usually made of polyester network yarn, without twisting, and its strength is lower than polyester sewing yarn. It differs from ordinary sewing threads in that the edge-twisting threads are made of polyester filament without twisting, while the sewing threads are made of polyester staple fibers with twisting yarn. Liqi thread industry is an excellent manufacturer of low elasticity polyester silk sewing thread in China.

Polyethylene terephthalate (PET), a fibre-forming polymer, is prepared from pure terephthalic acid (PTA) or dimethyl terephthalate (DMT) and ethylene glycol (EG) by esterification, transesterification and polycondensation. It is a fibre made by spinning and post-treatment.

Varieties of polyester filaments yarn

Initial polyester yarn: Undrawn polyester yarn (conventional spinning) (UDY), semi-pre-oriented yarn (medium-speed spinning) (MOY), pre-oriented yarn (high-speed spinning) (POY), high-oriented yarn (ultra-high-speed spinning) (HOY)

Drawing polyester yarn: drawing polyester yarn (low speed drawing polyester yarn) (DY), full drawing polyester yarn (one step spinning drawing method) (FDY), full drawing polyester yarn (one step spinning method) (FOY) textured polyester yarn: conventional textured polyester yarn (DY), drawing textured polyester yarn (DTY), air textured yarn (ATY).

With a hand pull, POY can generally pull longer, while FDY pulls less. Because POY is a pre-oriented polyester yarn, without full stretching, the remaining elongation should be more than 50%, while FDY is a full-oriented polyester yarn, the remaining elongation is generally less than 40%, which is relatively stable.  

The difference between DTY and FDY is FDY yarn is now stretched below 3% after spinning nozzle and no longer deformed. The appearance of polyester yarn is smooth and non-bulky. The compactness between fibers is quite high. Generally, the cross-section is round (if the nozzle shape is not round, it has different shape depending on the shape of spinning nozzle), the air permeability is poor, and the handle is hard (relative to DTY). The silk-like characteristics of clothing are generally used.  

DTY: Polyester yarn raw materials generally use POY (spinning process is similar to FDY, but the elongation is high), after false twisting (continental deformation) processing, the polyester yarn fibers are separated into bulky sections in irregular shape, air permeability is better than FDY, hand feel is softer than FDY (general polyester yarn). At present, due to the development of ultra-fine and island polyester yarn, the use trend is mainly to grind.   

POY: Preoriented wire, full name: PRE-ORIENTED YARN or PARTIALLY ORIENTED YARN. It refers to the chemical filament with the degree of orientation between the non-oriented filament and the drawing filament obtained by high-speed spinning. Compared with non-drawn polyester yarn, it has a certain degree of orientation and good stability. It is often used as a special yarn for drawing false twist textured yarn (DTY).    

DTY: Drawing textured polyester yarn, full name: DRAW TEXTURED YARN. It is made of POY precursor yarn by stretching and false twisting. Often there is a certain degree of elasticity and shrinkage. FDY: Full drawn polyester yarn.

FULL DRAW POLYESTER YARN. The synthetic filament was further prepared by spinning and drawing. The fibers have been fully stretched and can be directly used in textile processing.   

POY: Pre-oriented polyester yarn: Abbreviated as winding polyester yarn made at a spinning speed of more than 3000 m/min. Its orientation is higher than that of conventional winding yarn and has a certain storage stability than that of drawing yarn bottom, but its crystallization is still very low.