IR coating or UV coating?
Quote:
Originally Posted by
doddsy
Had a chat with OB today, and my insurance ( coles). Cole happy to pay for OEM replacement, OB use the Chinese made XYG by default. Benefits as far as I have research include, stronger screen less open to scratching, plus Pilkington screens have a UV coating which keeps 30% of the heat out. Pretty important of a machine with so much glass.
little Pilkington quote.
"
Pilkington coated windshields reflect more than 30 per cent of the sun's energy (more than five times that of a standard glass). This particularly benefits the new generation of vehicles that are commonly designed with larger glass areas."
This business of "coatings" re windscreen glass has me puzzled.
I regard UV coatings, (Ultra Violet), as stopping fading of interiors and also reducing sunburn, but not really stopping what I call heat. To stop heat, one needs an IR, (Infra Red), coating and that is not so common, at least in EU spec vehicles. Here in North America, GM, Ford, and Chrysler plus the Japanese have what they call Low E or Low Emissivity glass. This is glass produced with something that blocks Infra Red. As such, penetration of the heat rays of the sun into the interior are reduced and that means a smaller air conditioner and hence reduced engine load and therefore better mileage - or more correctly, better fleet wide CAFE, (Corporate Average Fuel Economy) numbers.
What I am saying is that the Pilkington trade mark Optikool refers only to UV penetration, (or its reduction), but not to IR which I would sure like to have as well. To resolve the problem on the side glass, I was able to install IR shielding film, but that is not practical for the windscreen.
The link below relates to the film I used. I would really like to hear that Land Rover now has available a windscreen that has what is called here in North America, Low Emissivity properties, - that it shields one from Infra Red as well as UV.
DISCO3.CO.UK Photo Gallery - LR3 miscellaneous/Trolley Jack Adapter
The simple test for IR rejection is that the steering wheel does not burn your hands nor does the dash heat up. I had this type of windscreen in my 1992 Buick Roadmaster and 98 Chev Pickup so Low E or IR rejection is not something new.
The FFRR might have the Infra Red rejecting glass.
The link below suggests that the FF Range Rover from 2003 on wards has optional heat resisting glass available. It should, you can get sound, heated, and AK47 resistant glass as an option so IR should not be too much to ask for as I also see my 1992 Roadmaster listed.
The difference between the Roadmaster and the FFRR is that near the interior rear view mirror where the black is, there is no IR resistant metal coating that also blocks RF, (Radio Frequencies). Hence that is where you would locate one of the toll pass transmitters. The Roadmaster windscreen did not have this feature - why not - well no automated toll readers in those days.
My guess is that with the IR rejection option, one would see Siglasol rather than Optikool marked on the FFRR glass. This therefore sounds like for the 3 or the 4, we are limited to windscreens with UV rejection and a bit of IR rejection, but even in 2012, the true IR rejecting glass I had in my 1992 Roadmaster is still not yet available from Land Rover.
Re XYG, some degree of UV rejection is near impossible not to have in glass; even that Coke bottle dropped from heaven in that movie had some.
As you suspect however, and from what I have heard, Uluru thru XYG glass is just not the same as Ayers Rock thru a Series windscreen - something about the colour and shape, at least during the day. At night, the colour concerns are not so evident, just the shape.:eek:
https://www.sunpass.com/specialWindshields
