Does Car Tint Darken Over Time?

You may have noticed, or at least, think that you’ve noticed that your recently installed window tints are changing in shade slightly. Well, don’t worry; you’re not going crazy. You are in fact correct. After a tint is fitted, it will darken. Well, sort of, anyway.

As this darkening process happens so gradually, a lot of drivers don’t even notice it, so I salute your observation skills, friend. I should also add that there’s nothing to worry about when a tint starts to dim; it’s actually a good sign. It means everything is as it should be.

It won’t darken beyond the percentage you’ve asked for, so resist the urge to leave angry messages on your fitter’s answering machine. If anything, it means they’ve done a quality job, so leave them some happy messages instead.

Why Does Car Tint Darken Over Time?

Okay, so now that we’ve established it’s normal, and your windows won’t end up completely opaque, let’s discuss why it is exactly that tints darken over time.

The reason your windows exhibit this shifting shade is that the adhesive holding the tint film to the window is curing.

What does curing mean? Well, curing is similar to drying, but not quite the same. Drying refers to evaporation of the solvent in the adhesive, whereas curing refers to the chemical reactions that take place in order to transform the liquid into a solid.

As the curing commences, it appears to the human eye as the tint becoming darker, when in reality, the shade has been consistent. It’s only the adhesive that has changed.

Bear in mind that tint will darken no matter which type you’ve chosen. Ceramic, carbon, metalized, and dyed tints all require an adhesive layer, so each of them will exhibit a slight change in opacity as the adhesive dries and cures.

Once the curing process is complete, your windows will stop darkening, and over time, will actually start to get lighter, especially if your car is often exposed to harsh sunlight.

How long it will take for your tint to start fading depends on the type you chose. Ceramic and carbon are known to last the longest when properly cared for — we’re talking between 5-10 years. Metalized and dyed tint films will fade far sooner. It’s part of the reason that they’re a more affordable option.

Variables in Tint Curing Process

It’s impossible to give one clear-cut answer in regard to how long the curing process of your tint will take. It depends on a number of variables. But what I can tell you is that it’s normally between 2-3 days.

Here are some of the contributing factors to the tint curing duration…

Climate and Season

You’ll often hear that it’s best to get your tint installation booked during the summer months, and actually, that’s not bad advice. Lots of sunshine and hot air will speed up the curing process significantly. 

When the tint adhesive is applied during the cold and rainy months, you can expect that 2-3 day average to stretch out into the 2-3 week zone, which isn’t ideal.

Of course, the general climate of the area you live in will also have a huge effect on the curing process. The hotter it is, the faster the glue will dry out and begin curing. That said, moisture in the air can slow things down a great deal, so arid rather than humid climates are the best for the job.

Drying Technique

Some people only use air to help the curing process along, choosing to keep their tints out of the sun until they’re completely ready in order to extend the longevity of the tint, but it can draw the business out significantly.

Exposing your vehicle to both sun and air will fast track the process and get your tints as dark as they’re supposed to be in record time.

Size of the Windows

More tint means more adhesive, so it stands to reason that tints on larger windows like that of, say, a Jaguar S-Type, will take longer to cure than the tints on a Ford Fiesta.

Brand and Quality

The quality of the adhesive as well as the tint film can also have a huge impact on the curing time. High quality adhesives tend to cure a little faster than others.

In regard to the brand of tint and adhesive, each company is likely to do things slightly differently, meaning the curing duration will shift from brand to brand.

Tint Material and Opacity

The tint material and opacity determines how much sun can reach the adhesive, so high quality sun-blocking materials such as ceramic and carbon may actually take a little longer to cure.

Summing Up

You’re not just seeing things. The tint on your window does appear to get darker over the first few days or weeks after installation, but the key word here is “appear”. In actual fact, the tint remains the same shade. It’s the adhesive that changes. From there on out, your tint will ever so slowly get lighter as a result of sun bleaching.