Polyester is a synthetic fiber that is widely used in the textile industry. It is known for its durability, strength, and wrinkle resistance. Polyester yarns are made from polyester fibers that are either filament or spun. Filament yarns are made from long, continuous fibers, while spun yarns are made from short, staple fibers.

There are three main types of polyester yarn:

• Partially oriented yarn (POY): POY yarn is made from polyester fibers that have been stretched but not fully drawn. This gives the yarn a high tenacity and low shrinkage. POY yarn is often used in the production of filament yarns and spun yarns.

• Fully drawn yarn (FDY): FDY yarn is made from polyester fibers that have been stretched to their full length. This gives the yarn a high strength and modulus. FDY yarn is often used in the production of fabrics for apparel, carpets, and upholstery.

• Draw textured yarn (DTY): DTY yarn is made from polyester fibers that have been stretched and then textured. This gives the yarn a bulky, soft hand. DTY yarn is often used in the production of fabrics for sweaters, fleece, and towels.

In addition to these three main types, there are also a number of specialty polyester yarns that are made for specific applications. These yarns include:

• Monofilament yarn: Monofilament yarn is made from a single polyester fiber. It is used in the production of fishing line, thread, and other applications where a strong, thin yarn is required.
• Multifilament yarn: Multifilament yarn is made from two or more polyester fibers that are twisted together. It is used in the production of fabrics, ropes, and other applications where a strong, durable yarn is required.
• Spun yarn: Spun yarn is made from short polyester fibers that are cut and then spun together. It is used in the production of fabrics, yarns, and other applications where a soft, comfortable yarn is required.

Polyester yarns are a versatile and durable material that can be used in a wide variety of applications. The different types of polyester yarns available offer a wide range of properties to meet the specific needs of each application.