Polynt Polycor Topcoat (White) is a high quality, Lloyd’s Approved, isophthalic polyester topcoat. This brush topcoat has been specially formulated for finishing applications, making it is easy to use with highly controlled thixotropic properties which provide high resistance to sagging. This product has superior gloss retention and resistance to yellowing over time.
Similar to Gelcoat, Polyester Topcoat contains wax solution which allows it to cure without leaving a tacky finish when applied to the exposed side as a resin rich outer layer. It is ideal for gelcoat boat repairs, in wooden boat sheathing or as the finishing coat to a surfboard.
Please note: if you require a Roofing Topcoat, please look at our TriRoof Roofing Topcoat. Unlike other distributors, our roofing topcoat is specifically designed for use on Roofs / Balconies / Valleys and is much easier to roll out than general purpose topcoats.
Please Note: Catalyst/Hardener (not included) must also be added to the topcoat in order for it to cure.
For General Health Information, see section on hazards.
Working with Polynt Polycor Topcoat Polycor topcoat should be conditioned to a temperature of 15-25 ⁰C before use. Workshop & mould temperature should also be above 15⁰C but lower than 25ºC, as it will cure too quickly. Gently agitate the topcoat before use and allow to stand for a short period of time to regain thixotropy. Polycor topcoat is intended for brush application and has been specifically formulated to exhibit the correct resistance to drag on the brush, release air and level correctly.
Non-Sagging Brush grades should be applied at a covering rate of 500 to 550 g per sq.m. When properly applied, brush grades typically do not sag. The topcoat will not entrap air (porosity) when applied as per instructions.
Mixing Catalyst All topcoats require the addition of catalyst (hardener) to initiate the curing process. The quantity of catalyst is worked out as a percentage of the weight of the topcoat (e.g. 2% of 1kg topcoat = 20gm catalyst). Dispensers or weighing scales are advised for accuracy. Temperature plays a large role in the curing process – the higher the temperature, the faster the cure. As a general guide, 1.8% catalyst addition at 25ºC gives approximately a 8-13 minute pot life. Thorough mixing of catalyst into topcoat is very important. Stir thoroughly using a mixing stick to scrape any uncatalysed topcoat from the inner walls and base of the container. The hardening process begins immediately, so only add catalyst to a working quantity. Once catalysed, the topcoat gradually cures, taking on a jelly-like consistency in about 10-20 minutes before becoming hard in about 45-80 minutes at room temperature (about 20ºC). The curing process generates heat within the topcoat. Too much catalyst or large volumes of topcoat increases this heat. Over catalysing the topcoat (>3%) can cause the material to overheat and sometimes cause a fire.
Applying the Laminate • Mix a maximum of 2kgs at a time, enough for about 3 to 4 sq.m of coverage. • Ensure that the surface has been adequately abraded, cleaned down with acetone and dry. • Brush catalyzed topcoat onto the surface ensuring good coverage.