Window tints, window films, or energy control films—which is what we call them around the shop—are designed to control the amount of energy that is transmitted through your vehicle’s glass. Energy comes in the form of visible light, and the varying light wavelengths can have different damaging effects on the human body as well as your vehicle. Visible light is measured from 380 nm to 780 nm; the next stage, infrared light, is measured from 780 nm to 1 mm. UV light actually comprises 3 types, which are measured from 10 nm to 380 nm. UVA is fully blocked by our atmosphere. UVB can be blocked by a single pane of glass. UVC, however, can only be blocked by a UV inhibitor, and can significantly damage your skin and vehicle interior. Radiation, which can be further categorized into the Near-IR and Far-IR types, can cause skin to burn and even develop cancer—so it is imperative to take concrete steps to limit your exposure. See what the American Cancer Society says about protecting yourself from UV and IR here.
What are the different types of film materials?
Dyed Films: There are two types of this cheap material. Deep-dyed films are the better of the two, as the polyester material is dyed with color all the way through. This provides better durability in terms of scratching. A regular dyed film is a clear polyester material with the dye on outside. This is not very durable and looks especially bad if scratched. The issue with these films is that the dye actually provides no additional heat protection, and they can fade or change color very quickly. You will notice that these films typically carry no warranty at all, or a very short lifespan—about three years, say—because the manufacturer is betting on the owner selling the car before the film becomes an issue. We do not sell any dyed films in our shop.
HP Films: HP stands for High-Performance—or at least that’s what it meant thirty years ago. Dyed films were the first to enter the market, but demand quickly grew for films that would keep the heat out and look great at the same time. Accordingly, HP films are hybrids of dyed material that are typically supplemented with aluminum. This makes the film fairly reflective, like a mirror, and provides some level of heat deflection. The biggest problem with HP films is that they block the transmission of radio signals, such as cell phone signals, into and out of your vehicle. This is a significant issue, as modern passengers are bound to use their cell phones during a trip.
Carbon Films: Carbon is a fantastic technology in window tints as it doesn’t ever fade, eliminating the need for dyes. Carbon films were the first “color stable” films to enter the market, and they offer decent heat protection as well. While standard carbon can look quite hazy, the aesthetic quality of nano-carbon films can be quite impressive. In particular, high-end carbon films like STEK’s ACTION series use the smallest carbon particles available, resulting in the best optical clarity. Carbon films also block 99.9% of UV light, and offer some Near-IR protection.
Multi-Layered Films: With more than 200 layers of material—each as thin as a Post-It note—3M Crystalline is in a league of its own in terms of high-tech manufacturing. Crystalline offers excellent performance numbers and has a slightly reflective appearance. This product was first introduced to the market as the 3M Prestige Series for commercial buildings; the technology was later adapted for automobile use in the early 2000s.
Ceramic Films: Things are about to get a bit more complicated. There are so many things to know about ceramic films that I could write a whole book about them—but I’ll keep this as straightforward and easy-to-navigate as possible. Ceramic films will typically have carbon and tungsten and sometimes ATO (antimony tin oxide), as well as ITO (indium tin oxide) on occasion. Higher-end films will feature these materials as nanoparticles for better dispersion and optical clarity. Tungsten, which is inexpensive to manufacture, blocks some Near-IR—the more you add to a film, the more it blocks. ATO contains a bluish hue and blocks IR a little further down the light spectrum; this is also fairly inexpensive. ITO, which is much more expensive, has a greenish hue and effectively blocks Far-IR. STEK NEX series films are the first and only films that use graphene, which is an ultra-fast thermal conductor that dissipates heat extremely quickly. In terms of coloration, the natural colors of the elements indicate the best durability—so watch out for high-performance films that are dyed for a more true-black appearance. They will fade and discolor.
Multi-Sputter Films: This is the very best material when it comes to heat protection. This highly advanced process of dispersing many precious metals within the film gives the material a unique appearance on top of outstanding infrared heat rejection. The downside is that the cost of this technology is so high that it is not commonly used for automotive applications. STEK VISON 70S employs this technology to produce fifteen layers of sputter, but it is mostly used for flat glass commercial buildings so that they can qualify for ultra-efficient and green building incentives.
Fooling the meter: I know this sounds crazy, but some window tints are specifically formulated to “beat the meter.” In the tint world, cheap infrared blockage test meters are widely available. What do these tell you? Basically nothing. Tint manufacturers love to add a bunch of tungsten to their films to show high infrared blockage rates at exactly one specific point in the light spectrum; the machine shown in the aforementioned link, for example, measures infrared blockage at only 950 nm. The most important thing to keep in mind is that heat is transmitted through your glass at thousands of varying wavelengths. So producing a film that yields seemingly impressive numbers is actually not very difficult to do. If you’d like to see some real-world testing using heat lamps, please feel free to come down to our shop, where we can easily disprove these manufacturers’ misleading claims.
What makes a good installation? Just like in most things in life, preparation is key. We exercise a tremendous amount of caution to protect your vehicle, and make sure to clean the glass and surrounding gaskets as well as possible to minimize the risk of dust and debris getting caught under the film. You can rest assured knowing that we install protective covers over your seats and console, and that we mask off door panels and use soak rope to protect your valuable electronics from damage during the installation process. For many popular car models, we also keep an OEM glass on hand for templating and heat-shrinking. For example, we keep a Tesla Model 3 back window at the ready, as they often have issues with cracking. In a similar vein, we keep a new Honda rear glass in stock so we can tint without removing the rear spoiler. We don’t cut corners around here—if there’s a better way to do it, we’re already on it.
Can I have a clear film that protects myself and my car? What you’d be looking for is 100% VLT (Visible Light Transmission), which is not available. We do, however, have STEK NEX in 85% VLT: an almost completely clear film with spectacular performance. So if you don’t like the appearance of a dark film but still want powerful protection, NEX 85 is for you.
How dark should my tint be? This is really based on personal preference and the risks you may take by having too light or too dark of a tint. When it comes to modern high-performance films, the darkness of the material or VLT actually has very little, if anything, to do with performance. Cheaper entry-level ceramic films with a lower VLT may perform better, but they will also be compromised in quality, haziness, and clarity. These films can also ghost, as can be seen here. In the middle of the day, a dark tint will have virtually zero negative effect on visibility; in dark lighting conditions, however, lighter tints will definitely provide better visibility when looking outside your windows. However, if you leave your wallet or valuables in your car and are worried about a break-in, lighter tints do not provide much privacy. Overall, though, all tints will help in the case of an accident—if your glass shatters, your tint will provide protection from the shards that might fly through your vehicle.
Should I tint my car? My answer is yes. Protect yourself, protect your friends and family, and protect your vehicle.
Metropolitan Detail, USA