In addition to painting houses, paints are used to color automobiles, underground tanks, road markings, ships, and many other items.
The element of paints that is responsible for giving color to various applications are pigments. Pigments occupy a very important place in the paint industry with large numbers of the various varieties being used for different purposes. Paint pigments act as colorants in commercial, industrial and decorative applications. The different types of pigments for paints can be listed below:
Earth Color Pigments: They are obtained from natural sources and are classified as inorganic pigments. They are weather resistant, light and chemical resistant. Some examples of this category are Umber, Ocher, Swedish red, Bolus, etc.
Mineral Pigments: These are classified as synthetic inorganic pigments. Some of the pigments included in this category are chromium oxide green, titanium dioxide, the ultramarine variety of blue pigment, iron oxide yellow, nickel titanium yellow, etc.
Vegetable Coloring Pigments: These are obtained from natural organic pigments available in plants. Some examples that fall into this category are Saffron, Indigo, Alizarin red, Reseda, Woad, etc.
Synthetic Pigments – Some synthetic pigments also find their way into the paint industry. Phthalocyanine, Azo, Dioxazine are just some of them.
The pigment in paints not only acts as a colorant, but also offers protection to the lower surface against weathering and corrosion. In fact, it is responsible for holding the paint together. Specialty pigments are used for specific applications, such as providing metallic finishes to car bodies or providing long-lasting characteristics for road markings. In addition to pigments, paints contain binders and solvents.
The binder helps hold the paint layer to the substrate. Solvents, also called diluents, act as a medium in which the binder, additives, and pigments are dispersed as true solutions or as a colloidal dispersion. Pigment, binder, and solvent must be mixed in the proper proportions so that the end result is an attractive, continuous, even coat of paint. The Paint Technologist and Paint Technician work together to achieve the desired end product.
With industrial paint applications ranging from aerospace, coil, automotive to architectural and decorative, paint formulations must meet various technical criteria in addition to offering durability, opacity and ease of application. It is the job of the paint technologist to formulate the paint to predetermined standards and the paint technician responsible for its manufacture to ensure that the characteristics established by the paint technologist are achieved. Equipment commonly used in paint manufacturing includes ball or pebble mills, vertical and horizontal bead mills, and high-speed intensive agitators. The paint manufacturer can make use of various other machines available for this purpose. However, everyone’s efforts are aimed at obtaining the best quality paints!