A large proportion of the current 800 million dollar annual purchases of paint in the United States is employed as protective coating for metal. While simple pigmented linseed oil maintenance paints constitute a large proportion of this, an increasing volume of products based on synthetic resins combined with drying oils is finding its way into the industrial market because such materials can be “tailored” to suit the user’s requirements. Furthermore, many industrial finishes must be capable of rapid cure in order to fit into mass production manufacturing schedules.
Organic coatings largely owe their protective properties to the impervious character of the envelope they provide around the protected metal. Hence the physical properties of a coating are of the greatest importance. These include adherence to the metal, hardness and toughness to withstand impact and scraping, flexibility and the inclusion of environmental factors such as moisture or chemical fumes. In general a...
