What Are TR90 and Polycarbonate Frames?
TR90 and polycarbonate are two widely used materials in the eyewear industry, valued for their lightweight properties and structural durability. Understanding their composition and origin helps in assessing their suitability for various frame applications.
TR90 is a thermoplastic polymer developed by EMS-GRIVORY, a Swiss chemical manufacturer. It belongs to the family of polyamides (nylon-based), known for flexibility, fatigue resistance, and low density. It’s particularly favored in injection-molded eyewear frames because it combines strength with bendability.
Polycarbonate (PC) is a tough, transparent thermoplastic derived from bisphenol A (BPA) and phosgene. It was commercialized in the 1950s and is widely used in high-impact applications, including ballistic glass, industrial lenses, and safety gear. While polycarbonate is commonly used in lenses, it is also utilized for frame structures in performance and safety eyewear.
TR90 vs Polycarbonate: A Comprehensive Comparison of Material and Real-World Performance
Choosing the right material for sunglasses frames involves understanding both the underlying mechanical properties and how those translate to real-world performance. Below is a detailed technical comparison of TR90 and polycarbonate:
Density and Weight
- TR90: ~1.14 g/cm³
- Polycarbonate: ~1.20 g/cm³
The difference may appear minor, but in large-volume frames or wraparound designs, TR90’s lower density contributes meaningfully to comfort during prolonged use. According to EMS Material Database, TR90 maintains excellent stiffness-to-weight ratio, which is ideal for activewear sunglasses and important for sports and long-duration use.
Flexibility and Elastic Modulus
- TR90 (Grilamid TR): Flexural modulus approx. 1.3–1.5 GPa
- Polycarbonate: Flexural modulus approx. 2.2–2.6 GPa
Polycarbonate is significantly stiffer, making it more prone to stress-whitening or fracture at thin cross-sections. In contrast, TR90’s lower modulus allows it to bend under pressure and return to its original shape. This “memory” behavior has been demonstrated in ISO 178-certified bend recovery tests. So, TR90 offers higher resilience and deformation tolerance, reducing the risk of frame cracking during accidental impacts.
Impact Resistance in Use
- Polycarbonate: Izod notched impact > 850 J/m (ASTM D256)
- TR90: Approx. 600–750 J/m depending on blend formulation
Polycarbonate shows superior raw impact strength in lab settings and is often used in safety-rated eyewear. It withstands drop tests up to 2.0 m under EN 166 standards. However, TR90’s flexible structure helps absorb and distribute dynamic force across the frame, making it more reliable for everyday use where frames must recover shape after torsion or minor collisions. For sports and casual wear, TR90 performs well under moderate stress.
Thermal Stability and UV Resistance
| Property | TR90 | Polycarbonate |
| Glass Transition Temp (Tg) | ~155°C | ~147°C |
| Heat Deflection Temp (HDT) | ~110–120°C (ISO 75-2) | ~130°C (ISO 75-2) |
| UV Stability (ISO 4892-2) | Excellent with additives | Fair without coating |
TR90 maintains mechanical integrity and color stability even after prolonged UV exposure, while polycarbonate tends to yellow over time if not coated. In extremely cold conditions, polycarbonate may become brittle (below −20°C), whereas TR90 retains its shape and flexibility. These differences are critical for outdoor or alpine users.
Moisture and Chemical Resistance
TR90 has a water absorption rate of <0.2% (24h), compared to 0.35% for polycarbonate (ISO 62), which helps it maintain dimensional stability in humid environments. It also outperforms polycarbonate in resistance to sunscreens, sweat, and mild solvents — essential for sports or beach eyewear.
Manufacturing Considerations
- TR90 is easier to inject at lower pressures, supporting thinner designs and fewer defects.
- Polycarbonate requires higher molding temperatures and annealing to prevent internal stress cracking.
Long-Term Durability and Wearability
TR90 retains elasticity and resists fatigue cracking over time, making it highly durable for frequent use. Polycarbonate, while robust initially, may develop microfractures under chemical or mechanical stress. Both materials are hypoallergenic and biocompatible, but TR90’s lower residual monomer content and smoother finish make it more skin-friendly in long-duration contact.
Note: All material specifications and performance data are sourced from manufacturer technical datasheets (e.g., EMS-Grivory, Picoplast), ISO/ASTM standards, and independent material databases such as MatWeb. Performance may vary by formulation and production conditions.
In conclusion, TR90 demonstrates superior flexibility, UV and chemical resistance, and comfort-focused durability — ideal for activewear and everyday sunglasses. Polycarbonate remains valuable in high-impact safety applications.
Aesthetic and Design Flexibility: Style Options Compared
Eyewear is as much a fashion statement as it is a functional tool. The aesthetic potential and design flexibility of TR90 and polycarbonate play a key role in product development.
- TR90 supports a broad range of frame thicknesses, surface textures, and colors. Its low melt viscosity makes it ideal for high-precision injection molding, allowing for seamless hinges and minimalist bridges.
- Polycarbonate, being more rigid and less flexible, limits frame design to safer, more conservative geometries. Sharp corners or ultra-thin profiles may lead to stress points and whitening.
Customization Capabilities
- TR90 can be colored in-mass or post-processed, offering matte, glossy, translucent, and gradient finishes. These features are valuable in lifestyle and sportswear design.
- Polycarbonate is less versatile for decorative finishes and often needs coatings to achieve desired aesthetics.
Design Innovation
TR90 allows integrated nose pads, wraparound styles, and memory-shape frames. This opens possibilities for hybrid designs (metal-TR90 combinations) without compromising structural stability.
TR90 is the clear winner for fashion-forward, design-intensive products. Polycarbonate remains more suitable for protective eyewear where form follows function.
Price and Value: Which Material Offers Better ROI?
Understanding total cost of ownership (TCO) and ROI is crucial when comparing frame materials.
| Factor | TR90 | Polycarbonate |
| Raw Material Cost | Lower | Moderate |
| Processing Cost | Lower (easy to mold) | Higher (requires coating) |
| Average Lifespan | 2–3 years (everyday use) | 3–5 years (specialty use) |
| Design Versatility | High | Moderate |
| Common Use Cases | Lifestyle, reading, sports | Safety, prescription, tactical |
- TR90 frames are easier and cheaper to replace or produce in high volume, making them ideal for consumer-focused brands and fast-moving SKUs.
- Polycarbonate provides greater long-term performance in niche use cases, but frame replacement or repairs may be more complex due to its rigidity and cost of coating.
TR90 offers better ROI for brands focused on everyday eyewear. Polycarbonate justifies higher costs in high-risk, high-reliability applications.
TR90 vs Polycarbonate: A Quick Guide Based on Your Needs
Choosing between TR90 and polycarbonate depends on how and where the eyewear will be used. Below is a concise guide tailored to different user needs.
Everyday Consumers and Lifestyle Wearers
Recommended: TR90
For daily wear, commuting, or casual use, TR90 offers a lighter, more flexible frame with excellent comfort throughout the day. It resists UV degradation, holds shape under temperature changes, and feels smooth against the skin.
Sports and Outdoor Enthusiasts
Recommended: TR90 (for general use), Polycarbonate (for high-impact environments)
TR90 performs well for most recreational activities like running, hiking, or cycling due to its bend recovery, sweat resistance, and comfort under movement. For added stability during training or long rides, cycling glasses offers a sport-optimized TR90 frame. Julong also provides specialized goggles designed for high-impact motorcycling and extreme sports protection.
Safety and Industrial Use
Recommended: Polycarbonate
Polycarbonate meets regulatory standards like ANSI Z87.1 and EN166 for high-impact resistance, making it essential for factory, lab, or construction settings. Its rigidity and lens-frame integration capabilities make it suitable for environments where eye protection is mandated.
Extreme Weather Conditions
Recommended: TR90 (hot/humid), Polycarbonate (cold/rigid use)
TR90 maintains its shape and elasticity in humid or high-UV regions, while polycarbonate may be preferred in sub-zero conditions requiring structural stiffness, though brittleness can be a concern. For skiing or cold-weather sports, Julong offers heated and anti-fog goggles tailored for outdoor performance and visibility.
Still undecided? Explore our products to experience the difference in comfort, durability, and style firsthand.
