What is athermal glazing in a car

The transparency of automotive glazing is useful for providing visibility, especially at night and in bad weather, but has the disadvantage of free penetration of solar energy and subsequent heating of the passenger compartment to an uncomfortable temperature.

Even if the climate system is turned on in the car, then it does not need any extra overload, not to mention fuel consumption, and when parked with the engine turned off, such an attack of infrared radiation can turn into a disaster, up to the destruction of interior elements.

It is desirable to delay part of the light before entering the cabin, that is, darken the windows.

Are athermal tinting and glass the same thing?

To prevent the penetration of excess light energy into the interior, it is enough to apply a light-absorbing film to the glass. Stick or even spray in a vacuum.

This will give a certain effect, but at the same time a number of disadvantages are formed:

• the strength of such a coating in any case leaves much to be desired, since any film does not have the properties of glass, it can be damaged, peel off or simply grow old;
• radiant energy will be absorbed more than reflected, which will lead to its accumulation and, ultimately, to undesirable heating of the cabin;
• if you increase the reflectivity of the applied surface layer, then such glass will begin to glare, which is unacceptable according to safety requirements;
• most budget films work uniformly at best in all ranges, infrared (IR), visible and ultraviolet (UV), although the ideal is to suppress the extreme frequencies of the entire spectrum, while maintaining transparency in its visible part.

For these reasons, it is best to introduce substances responsible for reflection and absorption during the glass manufacturing process, distributing them throughout the mass of the material, which is done in the case of real athermal glasses.

What glasses are athermal

The production of truly high-tech athermal glasses began relatively recently, they were put only on premium cars as optional equipment.

An intermediate solution can be considered a reduction in the optical transparency of the windshield, it is always made using the triplex technology, that is, two glass layers, between which a plastic flexible film is glued.

It is she who can be toned, like the one that is glued on the outside. Issues of strength and wear resistance will be resolved, but other problems will remain.

Therefore, only glass can be considered truly athermal, into which atoms of metals and their compounds are introduced uniformly throughout the mass. Silver or iron oxides are used.

The resulting effect allows, due to a change in the optical properties of the product, to spread the transmittance unevenly over the spectrum, lowering it in the required ranges.

Glasses can be of varying degrees of transmission, which is reflected in their factory markings.

1. tinted - glasses of moderate light transmission are provided with such a designation, they are distinguished by a slight greenish tint, retaining about 10-15 percent of the light flux of the visible range, while quite confidently cutting off up to half of the thermal energy and almost all short-wave energy in the UV range.
2. Overtinted - the visible part of the spectrum loses more than 20% of the intensity, nevertheless, the glass fits into the requirements of the domestic GOST for the light transmission of automobile glasses. Accordingly, the glass itself looks more shaded, having a fairly rich green tint.

Silver ions in the glass melt give the best effect, while negatively affecting the cost of the product.

Athermal tinting. The film is in accordance with GOST.

An additional disadvantage will be a decrease in the radio transparency of the glass precisely in those ranges where numerous automotive gadgets operate, which are responsible for navigation, control of driving modes and mobile communications.

But the glass becomes stronger, effectively protects the interior from heat and does not accumulate energy in itself, reflecting it in the opposite direction.

Pros and cons of safety glasses

The use of athermal glazing cannot consist of mere advantages, the complexity and imperfection of manufacturing technologies affect.

It is impossible to create a perfect optical filter around a car.

1. The production of athermal glasses, even not the most perfect ones, is expensive, their price is at least twice the cost of ordinary ones, regardless of whether it is triplex or tempered side and rear ones.
2. Despite all efforts, visibility through athermal glass is still deteriorating, which necessarily affects traffic safety in low light conditions.
3. There is some distortion of the color rendering of the glasses, a drawback inherent in any optical filter.
4. Difficulty in radio communication inside the car. Sensitive devices have to be taken out of it.
5. There may be problems with current legislation if the glass is not properly certified.
6. The type of shading may not be compatible with the driver's polarization-based sunglasses.

NEVER ADHES AN ATHERMAL FILM TO THE WINDSHIELD OF A VEHICLE

At the same time, the advantages of such glazing outweigh all its disadvantages.

1. The interior of the car lasts longer in conditions of strong solar radiation, you can use cheaper materials that would quickly become unusable with ordinary glass.
2. Fuel is saved due to a more gentle operation of the climate system.
3. The interior of the car does not overheat in parking lots, it can be cooled down faster before the trip.
4. The driver does not have to strain his eyesight, and the likelihood of glare is also reduced due to softer scattering of rays.
5. During operation of the heater, although slightly, the heat dissipation by radiation into the surrounding space is reduced.

The advantages of such glazing are so great that many car owners tend to install it on those cars where it is not provided by the factory.

How to distinguish a fake from an original

First of all, good glass cannot be cheap, for example, practically the same price as standard glass.

There are other, direct and indirect signs:

• the goods must be of high quality, especially for the edges of the glass, there should not be any violations of geometry, notches and irregularities;
• glass should not introduce optical distortions, which is ensured by the absence of thickness differences, the picture through the glass is exactly the same as without it, no “distorted mirror” effects;
• glass marking is applied clearly, fully corresponds to the sample provided by the manufacturer;
• the glass is certified, the documentation for it should not arouse suspicion;
• the manufacturer must be well known, small companies do not own such technologies;
• the shadow from quality glass looks darker than one would expect, looking at its visual transparency;
• usually light passing through athermal glass is polarized, which can be seen through polarized glasses, noticing the characteristic iridescent stains.

Only with real certified glasses can problems with regulatory authorities be avoided.

A fake most likely will not pass the light transmission test, as happens with the prohibited tinting of the windshield and front side windows.

And its strength will affect the safety of the car, in which the glued windshield works in the overall system to ensure the rigidity of the entire body.