Grilamid: how can it be lightweight and resistant at the same time?
Introduction
When you hold an Out Of glasses frame for the first time, the first thing you notice is how little it weighs. Or rather: how it weighs almost nothing. And yet that same frame survives drops, scratches, temperature changes and years of intense use without deforming. How is that possible?
The answer is called Grilamid. And it’s one of the reasons we use it in almost all our products.
What is Grilamid?
Grilamid — the commercial name for TR-90 — is a thermoplastic polyamide adopted by aerospace and medical industries for its properties. It’s not just a type of plastic: it’s an engineered polymer with very precise physical characteristics, designed to perform under extreme conditions.
Its molecular structure is built to absorb impacts without breaking, to elastically deform under pressure and return to its original shape, and to withstand thermal variations without becoming brittle or soft.
Grilamid: lightness and low density
Grilamid has a very low density compared to other technical polymers and metals. In practical terms: at equal volume, it weighs significantly less. For a glasses frame, this makes an enormous difference — not just in absolute grams, but in comfort during hours of sports use.
Anyone who has ever worn heavy glasses during an MTB session knows how the pressure on the nose and ears becomes a distraction. With Grilamid, that problem simply doesn’t exist.
Why is it resistant, despite the reduced weight?
This is where it gets interesting. Grilamid is classified as a material with extremely high impact resistance — superior to standard polycarbonate and many traditional polymers. This is possible thanks to its semi-crystalline structure, which distributes impact energy along the entire molecular chain instead of concentrating it at a single point.
In practice, instead of breaking like a rigid material would, Grilamid momentarily “bends” and then returns to its original shape. It’s the same principle that makes bamboo more resistant than solid wood beams: flexibility, used correctly, is a form of resistance.
What happens at extreme temperatures?
Another strength of Grilamid concerns its thermal behavior. Many plastic materials become brittle in the cold and soft in the heat. Grilamid maintains its mechanical properties across a very wide temperature range — this makes it ideal for mountain use, where you can go from -15°C on a descent to +20°C in the valley within a matter of minutes.
Ski goggles and sports glasses have to deal with these swings every day. Using a material that doesn’t stiffen in the cold or deform in the heat is a technical choice, not an aesthetic one.
Grilamid vs other materials: a direct comparison
Compared to standard nylon, Grilamid is lighter, more flexible and more impact-resistant. Compared to common rigid polymers (such as certain types of polycarbonate), it has a lower density and more elastic behavior. Compared to lightweight metals like aluminum, it weighs less and doesn’t corrode, while obviously being less rigid.
For sports glasses frames — where lightness, comfort and the ability to survive accidental drops are absolute priorities — Grilamid is hard to beat.
Why Out Of uses it
At Out Of, the choice of materials is never arbitrary. Every component of our products is selected after identifying the precise requirements it must meet. For sports glasses frames, those requirements are: minimum weight, maximum impact resistance, dimensional stability across temperature changes, and long-term durability.
Grilamid meets all four. That’s why you’ll find it across our entire lineup, from MTB glasses to ski goggles.
Conclusion
Lightness and resistance are not opposing qualities — they are qualities that depend on the choice of material. Grilamid proves that with the right molecular engineering, it’s possible to have both. It’s one of those technical details you never see, but that you feel every time you put on a pair of Out Of glasses.
