How to distinguish reflective film from endothermic film?

2019-05-08

Reflective film can increase the reflectivity of optical surface. Generally, metals have large extinction coefficient. When light beam is incident from air to metal surface, the amplitude of light entering metal decreases rapidly. As a result, the light energy entering the metal decreases correspondingly, while the reflected light energy increases. The bigger the extinction coefficient is, the faster the attenuation of light amplitude is. The less light energy enters the metal, the higher the reflectivity is.


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People always choose those metals with high optical coefficient and stable optical properties as metal film materials. Aluminum is commonly used in ultraviolet region, aluminum and silver are commonly used in visible region, gold, silver and copper are commonly used in infrared region, in addition, chromium and platinum are often used as film materials for some special films. As aluminum, silver, copper and other materials are easy to oxidize in the air and reduce their performance, they must be protected by dielectric film. The commonly used protective film materials are silicon monoxide,magnesium fluoride,silicon dioxide,aluminum oxide.


Related protective film materials from ATS:


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The following is a brief introduction to how to distinguish between endothermic and reflective membranes.


Method 1: It can be identified from the test method. Since there is no problem of heat saturation in the reflective insulation film itself, no matter how much power the reflective insulation film is irradiated by tungsten iodide lamp (at least 500W, preferably 1000W) for how long, the insulation effect will not be affected, while the endothermic film can not be irradiated by high-power tungsten iodide lamp for too long, so the power of tungsten iodide lamp for testing by many distributors of the endothermic insulation film will not be very high. Moreover, the test time is strictly limited, because the insulation effect of endothermic insulation film will be gradually lost if the irradiation time is a little longer.


Method 2: Reflection test. Because the reflective insulation film is insulated by reflecting infrared rays, you can choose a small piece of glass, paste the anti-thermal insulation film, then put the glass before the heat source of the test, and then rotate the angle of the glass to feel with the face at the same time, you can clearly feel that the glass will reflect heat to the face; Similarly, replace it with an endothermic insulation film, the same method of testing, will not feel. The heat is reflected.


Method 3: Degumming test. The endothermic insulation film uses the endothermic glue to absorb heat, so it can be distinguished by removing glue. Firstly, an endothermic and reflective insulation film is taken at the same time. The film is removed by alcohol, carburetor cleaner, tar cleaner or professional degumming agent, and then tested. At this time, it can be found that the thermal insulation performance of the endothermic insulation film no longer exists. The thermal insulation effect of reflective insulation film has hardly changed.