PPF Film Turning Yellow? The Material's Chemistry

A white or light car with PPF film on the bonnet can, after a few years, look as if brushed with a thin layer of tea – the film loses its clarity and turns yellow to brown, and it shows most against the light or next to unprotected paint of the same colour.

Whether it happens to your film, and how fast, comes down mainly to what it is made from: cheaper films darken towards yellow in the sun over time, dearer ones stay clear. The environment the car drives and sits in only speeds the pace up or slows it down.

What can be done about it and what can't

A yellowed film can't be cleaned back. Polishing and restorer products do nothing – the substance of the film itself changes colour, not just its surface. Once yellowing has set in, it stays in the film.

The good news is that the paint underneath is not affected – once the film comes off, the paint is in the state it was in when you had it applied. The answer is therefore a new film, not paint correction.

When it shows: with a cheaper film in everyday driving on Czech roads, the first hint tends to appear after two to three years as a warmer tint to the paint, and after five years or more the yellow to brown colour is obvious. That comes from the cars that pass through our workshop, not from an estimate in a table.

What makes a film that doesn't yellow different

Films differ in the raw material they are made from. In quotes this hides behind two words – aromatic and aliphatic. The first is cheaper and in the sun gradually stops being transparent and darkens towards yellow; the second stands up to the sun and stays clear.

This isn't a difference in marketing but in the price of the material: the raw material for the more durable one costs roughly three to five times more, so a film sold at a lower price is almost always built on the cheaper one. When two quotes come out strikingly differently, this tends to be the reason.

Nobody expects you to tell them apart – we recognise it for you from the film's name and from the manufacturer's documentation. With PPF film from us we tell you in advance which film we are putting on the car and what to expect from it years later.

Why a car in the city yellows sooner

The sun isn't the only thing acting on the film. A cheaper film carries an additive that protects it before it even reaches the car – and it is that additive which reacts with exhaust fumes and colours the film itself. That is why a car in the city centre yellows sooner than a car with the same sun exposure out in the country.

A dearer film doesn't need that additive, so city traffic doesn't act on it this way. If your car stands in a city street during the day, that is an argument for the dearer film, not against film as such.

How we recognise it for you

You won't measure a film's colour stability yourself, and nobody tells it at a glance from the paperwork with a quote. There is a lab test that ages a film artificially and measures how much it changes colour – whoever makes film honestly has its result, and we know how to ask for it.

You will not be running this test. Send us the quote you have on the table and we'll tell you what film is in it and what that means five years from now. A low price with no evidence of durability at all is almost always the cheaper option.

And if your film is already yellowing on the car, bring the car to our studio or send a photo of the bonnet against the light. We'll tell from that whether the problem is in the film or in something on the paint underneath.

When you don't want film

If the price of a quality PPF film doesn't appeal to you and what you're really after is the paint standing up to light wear and the sun, it's worth looking at ceramic surface protection.

Ceramic protection isn't a film and doesn't have this problem: it doesn't yellow and the paint colour underneath stays as it was when the layer went on. What it can't do is the main thing film does – stop a flying stone chip.

What happens next

With PPF film we base the price on the surface area of your particular car.

Write to us telling us which quote you are comparing, or send a photo of the film that is already on the car. We'll tell you what follows from it for you and whether it pays to change the film now or wait.

Ask about PPF film