These are the colouring materials added to the paints in order to impart a desired shade and colour. They are added in the finely powdered state. Table 10.3 shows the colouring pigments that are used for a particular colour.
Table 10.3 Colouring Pigments Used for a Particular Colour
| Colour of paint | Pigments |
|---|---|
| Black | Graphite, lamp black, ivory black, vegetable black |
| Blue | Indigo, Prussian blue |
| Brown | Burnt amber, raw amber |
| Green | Chrome green, copper sulphate |
| Red | Carmine, red lead, vermilion red |
| Yellow | Chrome yellow, yellow ochre, zinc chrome |
10.2.5 Solvents
They are volatile substances that are added to the paint in order to make their application easy and smooth. Solvents help the paint in penetrating through the porous surface. The most commonly used solvents are spirit and turpentine. Solvents are also known as thinners from their function of thinning the original paint which is highly viscous. They are added to reduce the property of paint blistering.
They also help the paint to penetrate through the porous surface and they increase the spreading power of the paint. After application, the solvent evaporates and the resulting surface is more even and smooth.