Textile wet processing can be thought of having three stages, pretreatment (or preparation), coloration (dyeing or printing) and finishing. Finishing in the narrow sense is the final step in the fabric manufacturing process, the last chance to provide the properties that customers will value. Finishing completes the fabric’s performance and gives it special functional properties including the final ‘touch’.
But the term finishing is also used in its broad sense: ‘Any operation for improving the appearance or usefulness of a fabric after it leaves the loom or knitting machine can be considered a finishing step’.1 This broad definition includes pretreatments such as washing, bleaching and coloration. In this book the term finishing is used in the narrow definition to include all those processes that usually follow coloration and that add useful qualities to the fabric, ranging from interesting appearance and fashion aspects to high performance properties for industrial needs. This definition may be applied to similar finishing processes for grey fabrics (without coloration). Bleaching and carbonisation are chemical treatments that also improve the quality of fabrics. They are not treated in this book because they belong typically in pretreatment, although there are rare exceptions.
Most finishes are applied to fabrics such as wovens, knitwear or nonwovens. But there are also other finishing processes, such as yarn finishing, for example sewing yarn with silicones and garment finishing (see Chapter 2.2.5). Textile finishing can be subdivided into two distinctly different areas, chemical finishing and mechani- cal finishing. Chemical finishing or ‘wet finishing’ involves the addition of chemicals to textiles to achieve a desired result (see Chapter 2). Physical properties such as dimensional stability and chemical properties such as flame retardancy can both be improved with chemical finishing. Typically, the appearance of the textile is unchanged after chemical finishing. Mechanical finishing or ‘dry finishing’ uses mainly physical (especially mechanical) means to change fabric properties and usually alters the fabric appearance as well. Mechanical finishing also encom- passes thermal processes such as heat setting (thermal finishing). Typical