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Flooring reference

UV & yellowing

What sunlight changes, and what a clearcoat can protect.

UV through a clearcoatSunlight reaches a clear wear coat and some schematic rays continue into the epoxy below. A second area illustrates reduced transmission by an engineered assembly.

  1. Step 1. Why epoxy can turn amber

    Light can trigger oxidation that changes how epoxy absorbs visible light, producing a yellow or amber appearance. Weathering can also reduce gloss and damage the surface. Heat-driven oxidation can discolor some epoxies without sunlight.

    UV through a clearcoatSunlight reaches a clear wear coat and some schematic rays continue into the epoxy below. A second area illustrates reduced transmission by an engineered assembly.
    Clearcoat stability and UV shielding are different properties. Arrows are schematic.

  2. Step 2. Clear is not the same as UV-blocking

    A clearcoat can resist its own yellowing while transmitting UV to the epoxy below. Ask for color-retention evidence for the complete assembly, especially with pale or metallic finishes. A new clearcoat cannot chemically reverse existing epoxy yellowing.

  3. Step 3. Choose an engineered protection package

    UV absorbers intercept relevant light; HALS help limit radical reactions; antioxidants address oxidation pathways. These roles can complement each other, but compatibility matters. Choose a formulated or supplier-approved system, not an improvised additive dose.

  4. Step 4. Match the system to the sunlight

    Sunlit interiors and outdoor floors need exposure-appropriate assemblies. Windows are not a universal UV shield. Request the actual colors, layer thicknesses and weathering conditions tested. Laboratory hours do not convert universally into outdoor years or a lifetime guarantee.

Sources
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