Term: opacity

In painting, opacity refers to the ability of a paint to hide or cover the surface beneath it. A paint with high opacity will effectively obscure the color or pattern of the substrate (such as a previous paint layer, primer, or bare surface), requiring fewer coats for full coverage. Conversely, a paint with low opacity is more transparent and may need multiple coats to achieve the desired finish.

Opacity is influenced by factors such as:

• Pigment quality and concentration
• Paint formulation (binder and additives)
• Application method and film thickness

In Australia, opacity is often tested and rated according to AS/NZS 2311:2017 standards for paint application. High-opacity paints are especially valued in professional and commercial painting for their efficiency and cost-effectiveness.