What kind of paint was used on old cars?
Old cars were painted mainly with nitrocellulose lacquer in the early-to-mid 20th century, then with enamel finishes as manufacturing shifted, and today most cars use polyurethane-based basecoat/clearcoat systems.
Over the decades, paint chemistry tracked advances in materials science: lacquer dried quickly to produce a deep gloss but wore down under heat and sun; enamel offered greater durability and resistance but required longer cure times; polyurethane-based systems introduced in the late 20th century deliver long-lasting color, UV protection, and a two-stage basecoat/clearcoat. This article traces that evolution, why restorers debate authenticity versus modern performance, and what it means for maintenance of classic vehicles.
Historical overview of automotive paints
The following timeline highlights the main paint types used on mass-produced cars from the 1920s through the late 20th century, including key characteristics and restoration notes.
- Nitrocellulose lacquer (1920s–1950s). This was the standard factory finish for several decades. It dried quickly, offered a high-gloss appearance, and was relatively easy to spray and polish. Its drawbacks included softer finish durability, sensitivity to heat and solvents, and limited chemical resistance, which meant finishes could yellow or crack with age. In restorations, lacquers are often chosen for period authenticity, and many enthusiasts recreate that classic look with modern lacquer formulations or compatible topcoats.
- Enamel finishes (1950s–1980s). Enamel—usually alkyd or later acrylic enamel—provided greater hardness and chemical resistance than lacquer, with improved durability. It dried more slowly and could require longer cure times, but it resisted yellowing and chipping better than lacquer. In the later years of enamel usage, two-stage processes (color coat plus clear or sealant) became common, paving the way for modern basecoat/clearcoat systems.
- Polyurethane-based finishes and basecoat/clearcoat systems (late 1970s–present). Modern factory finishes largely rely on pigment-containing basecoats protected by a polyurethane clearcoat. These finishes offer excellent UV resistance, durability, and color fastness, and they form the basis for today’s two-stage or multi-layer processes. Restorations of very old cars that aim for contemporary durability or easier maintenance often use polyurethane systems, though purists may seek period-correct lacquers for authenticity.
The shift from lacquer to enamel and then to polyurethane reflected improvements in cure speed, durability, UV protection, and ease of mass production. For collectors and restorers, the choice between authentic-looking lacquer finishes and modern, durable coatings depends on goals—historical accuracy, ease of maintenance, or long-term value.
Safety and restoration considerations
Working with old car paints requires awareness of hazardous materials and proper handling. Many pre-1980s finishes contained lead pigments and other hazardous metals, and older solvents were highly volatile. Always prioritize ventilation, personal protective equipment, and compliance with local environmental regulations when stripping, sanding, or repainting classic vehicles.
Lead-based pigments and solvent risks
Lead pigments were common in early automotive paints. Even if the lead is sealed beneath newer coats, disturbing those layers can release lead dust or fumes. Use appropriate PPE, containment, and removal methods; consider professional refinishing for authenticity and safety. Testing for lead content can inform the restoration approach and regulatory requirements in your area.
Summary
In short, the paint on old cars evolved from nitrocellulose lacquer to enamel and then to polyurethane-based basecoat/clearcoat systems. Lacquer dominated early decades for its gloss and ease of use, enamel offered improved durability in mid-century, and modern finishes favor polyurethane for longevity and protection. Restoration decisions balance historical authenticity with practical durability, safety considerations, and the desired look of the vehicle.
