Infrared selectivity for extruded PC sheet

Graph showing NIR selectivity of PC at different percentages of Tosaf's IR5980PC masterbatch

Israeli materials company Tosaf has introduced a masterbatch that it claims adds highly highly effective infrared (IR) selectivity to extruded polycarbonate (PC) sheets used to shield interior spaces from excessive heat build-up, along with a masterbatch to increase flame retardancy of PC at low sheet gauges.

The flame retardant additive FR7607PC has claimed let-down ratio values of 5% to 7%, sufficiently low to achieve a UL94 V-0 classification at 1.6 mm (by comparison, PC modified with Tosaf’s established multi-purpose grade FR3997PC only meets the same specifications at 2 mm and above).

Suggested applications for the material include construction (current fire retardancy standards can be met with thinner and lighter PC sheets) and electronic applications (lower wall thickness injection moulded parts).

The company’s testing has demonstrated that the fire resistant additive does not affect transparency to visible light but slightly increases haze by up to 2%.

Developed for PC applications such as lightweight construction sheets, Tosaf’s IR5980PC is an IR selective masterbatch to prevent interior spaces from heating up excessively.

Administered at a rate of addition of 1% to 6%, this near IR (NIR) selective masterbatch is claimed to filter out a significant proportion of NIR radiation in the 700nm to 1500nm range.

Tosaf claims that masterbatch levels as low as 3% provide a good CF (Cooling Factor) value of 1.17 (the correlation between transparency to visible light and solar heat gain coefficient). PC sheets containing this masterbatch maintain their high transparency to visible light with a light greenish undertone.

IR5980PC can be directly added to PC granules in the extrusion process or coextruded.