Page 2 - FUNCTIONAL SHEETS
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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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