GP Gelcoat Resin

GP Gelcoat Resin is a white, high-gloss polyester surface-coating resin used as the outermost layer of FRP mouldings. It is applied to the mould face before the fibreglass laminate is built up, giving the finished part its visible, protective surface finish.

General-purpose resin (such as our GP Clear Resin or UPR) is designed to saturate and bind fibreglass reinforcement. Gelcoat is a thicker, thixotropic surface-coating resin applied directly to the mould with no reinforcement mixed in — it forms the outer skin and finish of a moulding, while general-purpose resin forms the structural laminate behind it.

Yes. It is supplied as a plain white, pigment-free gelcoat, but FRP Polyester Pigment can be blended in before catalysing to produce a coloured, glossy finish for boat hulls, bathware, panels or mouldings.

GP Gelcoat Resin is a general-purpose gelcoat without a specific UV-stabiliser additive package. Like any unstabilised polyester surface, it can gradually yellow or chalk under prolonged direct UV exposure. For parts requiring long-term outdoor colour stability, discuss UV-stabilised formulation requirements with our technical team before specifying.

Its TDS says it shields the laminate from moisture, abrasion and weathering, and positions it as a more affordable alternative to ISO or vinyl ester gelcoats for standard-duty work. It publishes no chemical-resistance or immersion test. Where the surface faces sustained water contact or outdoor service, review ISO Gelcoat; for aggressive chemical service, discuss a vinyl ester system.

Gelcoat is sprayed or brushed onto the mould surface first so that, once the part is de-moulded, it becomes the visible outer face. Applying it before lay-up lets it cure against the smooth mould surface, producing a glossy, ready-to-use finish without additional surface finishing.

Thixotropy lets the gelcoat resist sagging or running when applied to vertical or overhead mould surfaces, so it builds up to an even coating thickness rather than pooling at the bottom of the mould before it gels.

Gel time is 8.5 minutes. Full cure at room temperature, once catalysed with MEKP (around 1.5%), typically takes 1.5 to 2 hours. The current TDS does not publish a cobalt octoate dosage for this gelcoat — confirm the accelerator dosage with us before production.

Viscosity is approximately 11,000 cPs — much thicker than a general-purpose laminating resin, by design, so it clings to the mould surface. Styrene content is 30%, and purity is 100%.

It is supplied in 50 kg or 225 kg packs, with a minimum order quantity of 500 kg.

Please share the moulded component, surface-finish requirement, application method, expected quantity, colour requirement if applicable, and delivery location. This helps the sales team understand the requirement before preparing a quote.

No. This product is published as a polyester surface-coating gelcoat for the mould-facing layer. The structural laminate is built separately with the appropriate laminating resin and glass-fibre reinforcement.