9.1 INTRODUCTION

It is reckoned that paints have been used by humans for at least 15,000 years, most notable early examples being at Altamira in Spain and Lascaux in France. The impulses which drove Palaeolithic man in those first early days of consciousness to express his dreams, needs, ritual and religion in art and paintings is a fascinating story, but one which is beyond the scope of this book. There have been many milestones since in the history of coatings, demonstrating a remarkable sequence of technological innovation. By far and away the bulk of paints used during these 15 millennia could be classified as organic coatings. It is believed that new coatings technologies now coming to the fore and based on inorganic materials will be recognised by future generations as another key milestone. It is the purpose of this chapter to give the reader a flavour of the technologies used in inorganic coatings, their applications and the diverse possibilities for future new technologies.

Most of the polymer materials used in coatings during the past 40 or 50 years are organic, derived from petroleum products or from living things. Low cost starting materials and the enormous scope of organic chemistry to convert the available precursors into useful materials, and the properties of the resultant products are probably the most important reasons for this situation. Organic polymers are light in weight, most are excellent electrical insulators, resistant to corrosion and are relatively easily fabricated at moderate temperatures. Good mechanical properties...