TABLE OF CONTENTS Pigments were in use before the birth of civilisation. Coloured minerals, and materials such as charcoal, were used to colour the bodies and living spaces of primitive man. As his skill grew, the use of minerals expanded to include the colouring of pottery, ceramics, and eventually glass, and the preparation of mixtures with media such as natural oils, and other resinous materials, to make paints.
From these early beginnings of the use of paint for decorative and artistic purposes has come the highly technical and commercially important paint industry of today.
A pigment is a coloured or non-coloured, black or white, particulate compound which can be dispersed in a medium, resin, or polymer, without being dissolved or appreciably affected chemically or physically. When paint is applied as a thin film over a substrate, the dispersed pigment will absorb and scatter light.
Dyes or dyestuffs, on the other hand, are usually soluble in paint media and give transparent or translucent films. This property obviously limits the utility of dyes in the coatings industry to products such as inks and stains.
The primary use of coloured, black or white pigments is to produce films which when applied to substrates such as metal, wood or concrete give the substrate a uniform distinct colour. The colour is selected for aesthetic reasons and must be durable, without fading or darkening, and the film must last for some considerable time when exposed to a wide range of...
