CLOUD GEL INDUSTRY TEST RESULTS
These are the accelerated aging tests that the Cloud Gel has been subjected to by Suntek and its customers, and the results:
- HEAT: 160 °F (71°C) for one month results in a barely perceptible haze. After two months, haze is easily noticeable. There was no yellowing. The shift in the transition temperature is about 3°F (1.7°C) after one month. This has been the most difficult test.
This test, with a one month time period, is a standard one which was developed for vacuum coated glass like Low-E. There is some question as to how realistic this test is for Cloud Gel because the Cloud Gel will never reach l60°F (71°C) in use, due to its use in conjunction with Low-E; the glazing facing indoors; and its high reflectivity and low absorption when it is above its transition temperature. It has been experimentally verified that the Cloud Gel does not approach 160°F (71°C) in actual use.
- CLEAR/OPAQUE CYCLING: 2,000,000 cycles with no measurable change in any properties.
- FREEZE/THAW CYCLES: 100 cycles with less than 3°F (1.7°C) change in the transition temperature.
- UV: testing by class companies uses commercially available instruments such as the high pressure Zenon Arc Weatherometer or a QUV with fluorescent bulbs. The Cloud Gel has passed 100 hours on a Sunshine Weatherometer. These units do not have cooled samples, so the UV is reflected rather than transmitted through the bulk of the Cloud Gel Layer. For this reason, Suntek does not regard these tests as valid. They are far easier than actual field conditions.
- Using a Suntek-built accelerated ager with a medium pressure doped mercury lamp which is filtered to match the solar UV spectrum in Florida; with an intensity of 100 suns; and a cooled sample stage to keep the Cloud Gel transparent, there was less than 3°F (1.7°C) shift in the transition temperature after the equivalent of 30 years' exposure to Florida sunshine. There was no yellowing or haze.
The Suntek accelerated ager was built specifically to test Cloud Gel, just as we previously built an ager to test Low-E in the 1970's. This Cloud Gel ager subjects the sample to heat, UV, and clear/opaque cycling simultaneously because degradation mechanisms are more destructive when working simultaneously rather than serially.