Chemical Finishing of Textiles

W D Schindler, P J Hauser

• Publisher: Woodhead Publishing
• Year: 2004
• Print ISBN: 9781855739055
• eBook ISBN: 9781845690373
• Topic: Technology & Engineering
• Subtopic: Materials Science
• Index: Technology & Engineering

The role of the textile finisher has become increasingly demanding, and now requires a careful balance between the compatibility of different finishing products and treatments and the application processes used to provide textiles with desirable properties. In one comprehensive book, Chemical finishing of textiles details the fundamentals of final chemical finishing, covering the range of effects that result from the interplay between chemical structures and finishing products.After an introductory chapter covering the importance of chemical finishing, the following chapters focus on particular finishing techniques, from softening, easy-care and permanent press, non-slip and soil-release, to flame-retardant, antistatic and antimicrobial. Within each chapter, sections include an introduction, mechanisms, chemistries, applications, evaluations and troubleshooting. The book concludes with a chapter on the future trends in chemical finishing.Chemical finishing of textiles is an essential reference for all academic and industrial textile chemists and for those studying textile education programmes.- Discusses the advantages and disadvantages of every important type of chemical finish- Combines technical understanding and practical experience concisely- Essential tool to assist in the demanding challenge of chemical finishing for textiles

1

Introduction to chemical finishing

1.1 Wet and dry or chemical and mechanical finishing

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 mechanical 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 encompasses thermal processes such as heat setting (thermal finishing). Typical mechanical finishes include calendering, emerising, compressive shrinkage, raising, brushing and shearing or cropping, and especially for wool fabrics milling, pressing and setting with crabbing and decatering. A summary of mechanical finishing has recently appeared. ²

Often mechanical and chemical finishing overlap. Some mechanical finishes need chemicals, for example milling agents for the fulling process or reductive and fixation agents for the decatering of wool fabrics. On the other hand chemical finishing is impossible without mechanical assistance, such as fabric transport and product application. The assignment to mechanical or chemical finishing depends on the circumstance, if the major component of the fabric’s improvement step is more mechanical- or chemical-based.

This book will focus on the chemical finishing of textiles, the application of relatively minor amounts of chemicals (often < 5 g m^{− 2}) to, in most cases, both sides of the fabric. Subsequent chapters will discuss the importance of each specific finish, the chemical mechanism for the effect, the chemicals used to provide the desired properties, the application and fixation procedures, the relevant evaluation methods and trouble shooting tips. Processes that employ high levels of chemical application (15–50 g m^{− 2} and more), primarily as one-sided treatments, such as coating are addressed only briefly in Chapter 2.

1.2 The challenge and charm of chemical finishing

The proper formulation of chemical finishes requires consideration of several important factors: the type of textile being treated (fibre and construction); the performance requirements of the finish (extent of effect and durability); the cost to benefit ratio; restrictions imposed on the process by availability of machinery, proced...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright page
• Dedication
• Preface
• 1: Introduction to chemical finishing
• 2: Chemical finishing processes
• 3: Softening finishes
• 4: Hand building finishes
• 5: Easy-care and durable press finishes of cellulosics
• 6: Repellent finishes
• 7: Soil-release finishes
• 8: Flame-retardant finishes
• 9: Non-slip finishes
• 10: Antistatic finishes
• 11: Anti-pilling finishes
• 12: Elastomeric finishes
• 13: Finishes to improve colour fastness
• 14: Ultraviolet protection finishes
• 15: Antimicrobial finishes
• 16: Insect resist and mite protection finishes
• 17: Finishing with enzymes: bio-finishes for cellulose
• 18: Novel finishes
• 19: Actual and future trends in chemical finishing
• Index