UV Filter Against Yellowing in Clear Resin

What Causes Resin to Yellow?

Epoxy resins, like most plastics, can gradually discolour when exposed to sunlight or artificial UV sources. This yellowing happens as ultraviolet rays break down the resin structure, causing a visible shift in clarity. Over time, even indoor lighting can trigger this process, especially in clear or lightly tinted projects.

How Do UV Filters Protect Resin?

UV filters are stabilisers added to resin formulas to absorb or reflect ultraviolet light, slowing the effects of sun exposure and preventing the resin from turning yellow. High-quality clear resins, such as “Trasparente” Multipurpose Clear Epoxy Resin, include integrated UV filters designed to preserve the original clarity for years. Odourless options like “Icrystal” provide similar protection, making them reliable for surface coatings, jewellery, and artistic castings.

Practical Tips for Long-Lasting Clear Results

• Choose a resin clearly labelled as containing a UV filter.
• Consider application thickness: surface coatings and deeper castings may have different UV resistance needs.
• Minimise exposure to direct sunlight where possible, especially for items meant for indoor display or use.
• Follow the resin manufacturer’s guidelines for mixing and curing times to ensure full UV protection is achieved after hardening.