Epoxy gelcoat (TG-140) – Green – 7090 + Hardener 7091T

RESOLTECH 7090 / 7091T – High Abrasion Resistance Epoxy Tooling Gelcoat

The Resoltech 7090 system with 7091T hardener is a high-temperature epoxy gelcoat (Tg 141°C after the full post-cure cycle, per the Resoltech technical data sheet), designed specifically for producing tooling and structural composite parts that require the highest surface quality (such as prepreg moulds). The green version is the most popular choice for mould building, as it makes visual inspection easier when laying up the laminate plies.

Why is 7090 / 7091T the uncompromising choice?

• Extreme mechanical resistance: The gelcoat formulation guarantees high hardness (Shore D 90) and abrasion resistance, which significantly extends mould life over repeated demoulding.
• Vertical surfaces: Thanks to the special gel-form 7091T hardener, the system allows a coat thicker than 1500 µm to be applied without risk of sagging.
• Low toxicity: The 7090 formulation guarantees safer working conditions for the user compared with standard high-temperature systems.

🛠 ExaTec Pro-Tip: the lamination window is key

A correct chemical bond between the gelcoat and the laminate is key to mould durability.

Time to laminate: Subsequent plies (wet layup, infusion or prepreg) must be applied onto the 7090/7091T gelcoat within a window of 8 to 16 hours after application at 23°C.

Mandatory post-cure: Never attempt to demould the tool after curing at room temperature only. The mould must go through an initial cure cycle (e.g. 8h at 60°C) before separation from the plug, to avoid surface damage.

Manufacturer: Resoltech – a French manufacturer of epoxy resin systems with aerospace and marine certifications.