What Is Enamel Paint Made Of?

The Fundamentals of Enamel Paint.

Enamel paint is a high gloss, hard-drying film covering that varies in composition depending on the intended use of the product. Of the four basic components, solvents and binders constitute 90 percent of the formula, while pigments and additives make up the remaining 10 percent.

Solvents

The choice of which combination of solvents to use is based on their capability of dissolving the binders and their evaporation rate. The most commonly used are the aromatic hydrocarbons toluene and xylene and the ketones methyl ethyl ketone (MEK) and methyl isobutyl ketone (MIBK). Other solvents used are alcohol esters glycol ethers and aliphatic hydrocarbons (methane).

Binders

Binders are liquid polymers or resins, natural or synthetic, used in the formula to bind the pigment particles to the additives. Most common are natural or vegetable oils, alkyds and acrylics, vinyl acrylics, vinyl acetate/ethylene (VAE), polyurethanes, polyesters, melamine resins, epoxies and silicone.

Pigments

Pigments or dyes can be natural--clay, calcium carbonate, mica, silicas and talcs, or synthetic-- engineered molecules, calcined clay, precipitated calcium carbonate and synthetic silicas. Hiding pigments, used to make the paint opaque, include phthalo blue, iron red oxide and titanium dioxide coated with silicon or aluminum oxide.

Fillers

Fillers improve the physical quality of the coating by thickening, supporting the structure and increasing the volume of the enamel. Typical additives include diatomaceous earth, talc, lime, baryte, clay, fine quartz sand, biocides and fungicides, plasticizers, freeze/thaw stabilizers, surfactants, colloids and coalescing agents.

References

• Industry Sector P2 Notebooks: Metal Painting and Coating Operations
• Smithsonian Museum Conservation Institute: Painting Conservation Glossary of Terms

Resources

• American Coatings Association