You have spent hours for creating a clear and shiny resin piece, only to notice it yellowing over time - a frustrating experience for any resin artist or maker.
One of the most prevalent problems of epoxy resin, regardless of what you are making jewellery, coasters, river tables, or artwork, is yellowing. However the good news is that once you know how and why it occurs, why it can be prevented or remedied, you will have your resin projects remain crystal clear during the years.
Breaking down the causes, prevention measures and restoration alternatives of yellowing resin step by step.
Even excellent quality epoxy resins may turn a little yellow with time, yet there are other circumstances that accelerate the progress at an extreme rate.
The number-one culprit.
Exposure to UV light in the sun or fluorescent bulbs disrupts the chemical bond itself in epoxy leading to
oxidation and the appearance of yellow colour.
Common signs:
Storing or Curing resin under hot conditions causes oxidation to be quicker.
Regular warmth (such as that around a radiator or window) may cause the resin to age more rapidly.
Low-cost resins do not include UV stabilizers or optical brighteners that inhibit color change. In their absence the resin darkens naturally with time.
Using tools, moulds or pigments that are not clean or cannot be used with epoxy may cause impurities that colour the resin.
Excessive hardener or lack of even mixing leads to chemical instability and your resin will cure with a yellowish color immediately.
It is very much easier to prevent than restore. This is the way you will prevent your new resin project from turning yellow too soon.
Find UV-stabilized/non-yellowing epoxy (such as Epoxy Res-iT Premium Clear).
Such formulas contain UV absorbers and HALS (Hindered Amine Light Stabilizers) which are active in
photo-oxidation prevention.
Resin pieces should always be cured and stored in the shade and a cool place.
When it is displayed close to the window, UV-filtering glasses or acrylic covers can be considered.
Apply accurate proportions of resin to hardener (i.e. 1:1 or 2:1 according to formula).
Wanted tinting can be caused easily by inaccurate mixing.
Clear resin can be tinted with polluted cups, mixing sticks or old pigment.
Isopropyl alcohol wipe tools are used but allowed to dry completely before use.
A coating of a UV resistant varnish or clear finish can be used to offer an added protection to works subject to light, including tables or wall decorations.
Res-iT Tip: The Epoxy Res-iT Protective Gloss Topcoat is a durable UV barrier that maintains its clarity, which is best applied to furniture and pieces of decor.
In case your resin has already been yellowed, do not panic. It will depend on the depth of discoloration and the nature of the project you are working on, how much will be recovered.
In case it is light and confined to the surface:
This tends to bring back the light and shine.
For more visible yellowing:
In cases whereby the resin has stained in all parts, complete restoration might not be ensured. In this case:
This reduces wastage and allows you to make up the experience.
Even the highest quality resin may acquire a slight amount of warmth in several years. It is normal and in the nature of epoxy and what the aim of the process is to slow it down as much as possible.
To keep pieces clear:
When well kept, professional resin such as Epoxy Res-iT Pro Kit will be clear over many years without some apparent yellowing.
| Product Type | Use Case | Benefit |
|---|---|---|
| UV-Stabilized Resin | General casting, coating, and art | Resists sunlight and ageing |
| Protective Gloss Topcoat | Furniture, wall art, trays | Adds UV & scratch protection |
| Pigments & Tints | Correcting discoloration | Neutralize or enhance color tones |
| Cleaning Solutions | Tool maintenance | Prevent contamination or residue yellowing |
View the entire line of the non-yellowing resins and protective topcoats of Epoxy Res-iT on our web site, developed to be long-lasting and clear.
The main causes of the yellowing of resin are UV light, heating, or the absence of UV stabilizers in the formula. Inexpensive resins which are not properly inhibited oxidise more readily resulting in amber tones.
Apply an epoxy resin that has UV-stabilizers, put pieces that are already finished in places that are not exposed to direct sunlight, and apply a protective coating. Care must also not be overheated during the drying.
To fix minor surface yellowing, sanding, polishing or applying a UV-stable layer can be done. Prolonged inward yellowing is however not normally reversible.
Any resin can exhibit a case of slight warm color over a long period, although high quality and UV resistant resin such as Epoxy Res-iT Pro Kits can greatly retard the rate of yellowing.
Select an epoxy containing in-built UV blockers and HALS. The epoxy resin Res-iT Premium Clear and Deep Pour Resin are meant to withstand the effects of yellowing in the UK environment.
Yellowing of the resin is not unavoidable but disappointing. With UV-stabilized products, a clean workspace, and careful storage of your resin creations in the heat and sunlight, you can have years of crystal clear and professionally looking resin creations.
We make Epoxy Res-iT UK non-yellowing, high-clarity epoxy systems which are chosen by artists, makers and DIY users that are interested in the quality of their work to last.
Nothing less is due to your art.
Tobe
Thanks for the tips This really helped me understand how to prevent resin yellowing in my projects and keep my creations looking fresh.
Jan 06, 2026