Improper handling during production can cause premature aging of celluloid, indirectly reducing its UV resistance. Targeted optimization is necessary:
Controlling processing temperature and time.
High-temperature processes (120-150°C) such as hot pressing and shaping accelerate celluloid oxidation. Simultaneous exposure to natural sunlight can easily lead to premature degradation. Therefore, it is necessary to:
Use UV-filtering glass (filtering over 90% of UV rays) in the processing environment to avoid direct sunlight.
Shorten the high-temperature processing time (for example, reducing the hot pressing time from 30 minutes to 15-20 minutes) and introduce inert gas (nitrogen) during the cooling phase to reduce oxidation.
Post-processing and curing
The formed film is UV-cured: Expose it to low-intensity UV light (365nm wavelength, 50W power) for 2-3 hours to slightly cross-link the material’s molecular chains, forming a more stable structure and improving its resistance to UV aging (experiments have shown this can extend the weathering life by over 30%).