Orthophthalic Gelcoat (Black)

This black orthophthalic gelcoat is based on a standard orthophthalic unsaturated polyester resin and pigmented with carbon black for a deep, uniform black finish. It is designed for open-mold composite fabrication where a cosmetic black surface layer is required, including automotive body panels, industrial covers, electrical enclosures, and architectural profiles. The dense black pigment system provides full opacity at the standard film thickness of 0.4–0.6 mm. Cobalt pre-acceleration allows direct catalysis with MEKP at 1–2% by weight. The thixotropic formulation ensures no sag during vertical surface application when sprayed or brushed. At 20°C with 1.5% MEKP, gel time is approximately 25–40 minutes, with Barcol hardness exceeding 40 after full cure. The black gelcoat is compatible with standard polyester and vinyl ester structural laminates applied within the secondary bond window. Post-cure, the surface accepts painting, polishing, and adhesive bonding without primer in most applications. UV performance is limited compared to isophthalic grades, so exterior applications requiring long-term weathering resistance should consider an iso or NPG gelcoat. Supplied in pails and drums for production environments.