An Introduction to Textile Coloration

Principles and Practice

Roger H. Wardman

• Publisher: Wiley
• Year: 2017
• ISBN:
  9781119121589
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Organic Chemistry

An Introduction to Textile Coloration: Principles and Practice

The Publications Committee of the Society of Dyers and Colourists (SDC) has been aware for some time of the need to produce a book at an introductory level aimed at personnel working in textile dyeing or printing companies as well as those interested in entering into the field. The SDC runs a course for dyehouse technicians leading to the award of its Textile Coloration Certificate and this book is intended to be helpful for candidates following the course. Additionally, it will be helpful for professionals in textile companies who do not have a strong scientific background, so that they may attain a better understanding of the chemical principles of colour application.

Starting with the basic science underlying dyeing and printing processes, this comprehensive book explains the fundamentals of dye and pigment chemistry and the various application techniques and processes. It offers chapter coverage of the general chemistry related to textiles, textile fibres, chemistry of dyes and pigments, industrial coloration methods, textile printing, theoretical aspects of dyeing, the measurement of colour and fastness testing. Reference is made to developments that have taken place in the coloration industry in recent years, not least of which have been the challenges imposed by the drive towards environmentally-friendly processes and restrictions on the use of certain chemicals.

An Introduction to Textile Coloration: Principles and Practice

• Covers atomic structure, chemical reactions, and acids, bases, and salts
• Explains the nature of fibre-forming polymers and the conversion of synthetic polymers into fibre filaments
• Educates on the classification of colorants and the commercial naming of dyes and pigments
• Introduces readers to the dye application processes and dyeing machinery
• Instructs on dye aggregation, factors affecting colour appearance, the principles of colour fastness testing, and more

"…this is the sort of book any dyer, technician, student, academic will want to always have as an ready reference to everything pertaining to textile coloration."

Richard S. Blackburn, School of Design, University of Leeds, Leeds, LS2 9JT, UK

1
General Chemistry Related to Textiles

1.1 Introduction

This chapter provides a background to the chemical principles involved in coloration processes, which will be beneficial to those with little working knowledge of dyeing chemistry. Chemistry has been classically divided into three branches: inorganic chemistry, organic chemistry and physical chemistry. Inorganic chemistry is the study of elements and their compounds. However carbon is so unique in the breadth of the compounds it forms (chiefly with hydrogen, oxygen, nitrogen and, to a lesser extent, sulphur) that it has its own branch – organic chemistry. Physical chemistry is concerned with the influence of process conditions such as temperature, pressure, concentration and electrical potential on aspects of chemical reactions, such as how fast they proceed and the extent to which they occur.

There are no clear distinctions between the three branches. For example, organometallic compounds are important substances that combine organic and inorganic chemistry, and the principles of physical chemistry apply to these two branches as well. Fundamental to all these branches of chemistry is an understanding of the structure of matter, so the chapter begins with this important aspect.

1.2 Atomic Structure

Modern chemistry is based on the belief that all matter is built from a combination of exceedingly minute particles (atoms) of the various chemical elements. Many different elements are found in nature, each possessing characteristic properties; the atoms of any one element are all chemically identical. An element is a substance made up of only one type of atom, for example, carbon is only made up of carbon atoms, and sodium is only made up of sodium atoms. Atoms combine together to form molecules of chemical compounds. A molecule is the smallest particle of a chemical element or compound that has the chemical properties of that element or compound.

A single atom consists of a very dense central core or nucleus, which contains numbers of positively charged particles called protons and uncharged particles, called neutrons. Protons and neutrons have equal mass and together they account for the atom’s mass. A number of very small negatively charged particles, called electrons, circulate around the nucleus in fixed orbits or ‘shells’, each orbit corresponding to a certain level of energy: the bigger the shell (the further away from the nucleus it is), the greater the energy. These shells are labelled n = 1, 2, 3, etc., counting outwards from the nucleus, and each can hold a certain maximum number of electrons, given by 2n². The movement of an electron from one energy level to another causes the absorption or emission of a definite amount of energy. Atoms are electrically neutral, so the number of electrons in an atom is exactly the same as the number of protons in its nucleus. The total number of electrons within an atom of a particular element is called the atomic number of the element. This is the same as the number of protons in its nucleus. It is the arrangement of the electrons around the nucleus of an atom that determines the chemical properties of an element, especially the electrons in the outermost shells.

It is possible that some of the atoms of an element have a different number of neutrons in their nucleus, but their numbers of protons and electrons are still the same. These atoms are called isotopes, and although they have the same chemical properties as the other atoms, their atomic masses are different. Also recent research into atomic structure has shown that the three subatomic particles are themselves made up of other smaller particles such as quarks, but for this book it is sufficient to only consider atoms in terms of protons, neutrons and electrons.

The simplest atom is that of hydrogen, which has a nucleus consisting of just one proton with one electron orbiting around it and has a...

Table of contents

• Cover
• Title Page
• Table of Contents
• Society of Dyers and Colourists
• Preface
• 1 General Chemistry Related to Textiles
• 2 Textile Fibres
• 3 Chemistry of Dyes and Pigments
• 4 Industrial Coloration Methods
• 5 Textile Printing
• 6 Theoretical Aspects of Dyeing
• 7 The Measurement of Colour
• 8 Fastness Testing
• Appendix: Some Textile Terms and Definitions
• Index
• End User License Agreement