Transparent phone cases have become a favorite among users who love showcasing the sleek design of their phones. But one common issue never fails to appear over time—yellowing. At Sendtin Case, with over a decade of experience in precision injection molding and material engineering, we’ve studied this problem deeply and developed advanced anti-yellowing solutions that truly make a difference.
Why Transparent Phone Cases Turn Yellow
Most clear phone cases are made from TPU (thermoplastic polyurethane), a flexible, impact-resistant material. However, TPU’s chemical structure is sensitive to oxidation, UV light, and heat, which gradually break down the polymer bonds, leading to a yellow tint.
Scientific studies, such as those from Polymer Degradation and Stability Journal, confirm that UV exposure accelerates polymer aging, causing the visible color change.
Other contributing factors include:
- Heat and humidity: Both increase oxidation rates in TPU.
- Skin contact: Natural oils, sweat, and cosmetics can penetrate the surface, speeding up discoloration.
- Environmental exposure: Dust, smoke, and air pollution settle on the surface, further darkening the color.
According to market data from Statista (2023), over 60% of clear case users replace their cases within 6–12 months due to yellowing—showing how widespread this issue remains.
Can Yellowing Be Prevented?
While no clear material is 100% immune, Sendtin Case applies multiple protective measures to delay yellowing and extend product lifespan.
Our recommendations:
- Choose advanced materials: Hybrid TPU + PC cases or upgraded imported TPU from Germany resist yellowing far better than standard materials.
- UV-resistant coating: Sendtin applies a dual-layer anti-UV treatment that reduces oxidation by up to 40% compared with ordinary TPU.
- Regular cleaning: Mild soap and water can remove accumulated oils and dirt.
- Avoid heat exposure: Keep your phone away from prolonged direct sunlight or high-temperature environments.
In 2024, several of our OEM clients reported 30–40% longer clarity retention after adopting Sendtin’s anti-yellow TPU formula.
What to Do If Your Case Has Yellowed
Once yellowing occurs, it can’t be completely reversed because the polymer itself has degraded. However, some improvement is possible:
- Cleaning tip: Use a gentle mix of baking soda and water for surface refresh.
- Upgrade: Switch to hybrid cases designed for long-term clarity—our Sendtin hybrid series maintains transparency 50% longer than standard clear cases.
Why Brands Choose Sendtin Case as Their Anti-Yellowing Manufacturer
At Sendtin Case, we understand that yellowing isn’t just a material issue—it’s a brand reputation issue. When your customers see their case yellow within months, it affects trust in your brand. That’s why we’ve made anti-yellowing one of our core R&D focuses.
With over 10 years of OEM/ODM experience, a dedicated engineering team, and partnerships with premium raw material suppliers, Sendtin Case offers:
- Verified anti-yellow TPU and PC materials
- UV-resistant coating technologies tested in real-life environments
- Consistent color stability under heat and humidity
- Comprehensive customization support for branding, packaging, and structure design
FAQ
How long before a transparent phone case turns yellow?
Low-quality TPU cases may yellow within 2–3 months. Sendtin’s UV-protected TPU cases can remain clear for up to 12–18 months.
Is silicone better than TPU?
Silicone cases resist yellowing better but attract lint easily. Hybrid TPU-PC designs offer the best clarity and comfort balance.
Can yellowing be fully reversed?
No. Cleaning can improve appearance, but once oxidation happens, the material won’t return to full transparency.
Which material is best for anti-yellowing?
High-grade polycarbonate (PC) with TPU edges provides the best protection, clarity, and longevity.
Why choose Sendtin Case?
Because we’re not just making cases—we’re engineering clarity that lasts.
