Note: This post is part of a larger series on generic coating types. Click the button at the bottom of this post to download the entire guide.
Alkyds are sometimes referred to as oil-based coatings, or oil-modified polyesters. They are usually formulated from a combination of synthetic dyes and natural resins. These coatings are not generally recommended for exterior surface protection, due to their poor surface durability, limited corrosion resistance and tendency to break down easily under UV radiation.
- Easy to apply
- Certain formulation can achieve long-term color and gloss retention
- Often exhibit poor exterior durability
- Long cure times
- Poor UV resistance
Alkyd coatings are not recommended for use in corrosive environments. That doesn’t mean they do not excel in some light industrial situations. They are ideal for the color-coding of handrails, safety equipment, overhead piping and safety striping. They also are also well suited to substrates that carry electrical currents, such as transformers and breakers, transmission and distribution towers, substation steel and other such areas.
Alkyds bear the stain of once being predominantly formulated with lead pigments. Though they’re no longer made with this hazardous heavy metal, lead-based alkyds are still frequently encountered in jobs across the United States. Safely removing or overcoating these products requires a specialized set of procedures.