Polyester is a synthetic fibre derived from coal, air, water, and petroleum. Polyester fibres are formed from a chemical reaction between an acid and alcohol. In this reaction, two or more molecules combine to make a large molecule whose structure repeats throughout its length. Polyester fibres can form very long molecules that are very stable and strong. The four basic forms are filament, staple, tow, and fiberfill. In the filament form, each individual strand of polyester fibre is continuous in length, producing smooth-surfaced fabrics. In staple form, filaments are cut to short, predetermined lengths. In this form polyester is easier to blend with other fibres. Tow is a form in which continuous filaments are drawn loosely together. Fiberfill is the voluminous form used in the manufacture of quilts, pillows, and outerwear. The two forms used most frequently are filament and staple.
Polyester is used in the manufacture of many products, including clothing, home furnishings, industrial fabrics, computer and recording tapes, and electrical insulation. Polyester has several advantages over traditional fabrics such as cotton. Polyester is the perfect fabric for the application of water-, soil-, and fire-resistant finishes as it does not absorb water but oils. Its low absorbency also makes it naturally resistant to stains.
Polyester clothing can be preshrunk in the finishing process, and thereafter the fabric resists shrinking and will not stretch out of shape. The fabric is easily dyeable, and not damaged by mildew. Textured polyester fibres are used for filling pillows, quilting, outerwear, and sleeping bags. Polyester continues to be one of the top consumer products driving the US economy along with cotton and other fibres.