Page 2 - FUNCTIONAL SHEETS

IR PROTECTION

Along with the desire to lower energy bills, there has been more interest in polycarbonate sheet, which blocks infrared
wavelengths (IR) . The visible spectrum is in the range of 390-700nm, The UV light is below 390nm and the IR light
is above 700nm Sunlight can pass through windows, causing the interior of buildings and vehicles to heat up. Low-
wavelength light has more energy than high-energy light, causing faster heating. This means that visible light has
more energy than infrared light.

It is necessary to absorb or reflect light to reduce heating. There is so much energy in the visible zone that you can
only absorb, because by blocking the light, you make the window darker, that often contradicts the purpose
of the window. Besides making the window darker, another way to reduce heat build-up is to place IR absorbers in
the polycarbonate sheet to block IR light wavelengths Polybright sheets are able to offer three colors of IR blocking
polycarbonate sheet, each of which appears in different amounts and blocks IR light.

We currently have Grey, Light Green and Dark Green products. Gray and light green products aim to block out as little
visible light as possible and have only a slight tint. As a result, a moderate amount of warming still occurs in the visible
zone. There is a dark green product for further reduction of warming. The graph below shows transmission at various
wavelengths along the UV, visible and IR wavelengths.

IR Protected Polycarbonate - Transmission Curve

85
80
75
70
Light Transmittance (%) 55
65
60
50
45
40
35
30
25
20
15
10
5
0
280 380 480 580 680 780 880 980 1080 1180 1280 1380 1480 1580 1680 1780 1880 1980
Wavelength (nm)
<390nm UV, 390-700nm Visible, >700nm IR Dark Green 3mm Light Green 3mm Grey 3mm

It should be noted that the transmission curves
for thicker materials, such as 5 mm or 6 mm,
are almost the same.Transmission curves and
material samples for thicker material can be
obtained by contacting Teknorm Plastik. Other
than buildings, the main application of IR
Blocking Polycarbonate has been for farm and
forestry vehicle cabins.
Polycarbonate is used to provide protection and
IR absorbers reduce the heating of the cabin by
the sun.
In the cabins with modern equipment, there
are many electronics that also cause heating,
and when combined with the sun, they can
put a great load on the car’s air conditioning.
IR blocking polycarbonate has proven to be an
effective way to reduce the air conditioning load
on these vehicles.

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