Why Is Your Resin Turning Yellow? An Ultimate Guide

Resin turning yellow is a common issue for many artists and crafters when working with resin. Understanding the causes behind this phenomenon and learning effective prevention methods is crucial for anyone passionate about resin art.

Consider joining a resin art workshop to protect your resin art from turning yellow with hands-on experience and expert guidance on safeguarding your creations against discolouration. The knowledge gained from such workshops can empower you to elevate your resin skills while ensuring the longevity of your artwork.

This blog will explore why resin turns yellow and discuss practical prevention tips. By the end, you'll better understand how to preserve the beauty and integrity of your resin creations. So, let’s get into it!

Factors that Cause Resin to Turn Yellow

UV Light Exposure

UV light is a significant factor in the resin's turning yellow. The energy from UV rays can initiate a chemical reaction in the resin, leading to discolouration. Both natural sunlight and artificial UV sources contribute to this process.

UV rays can break down the chemical bonds in the resin, causing it to change colour over time. This is why resin art pieces placed near windows or under direct sunlight are particularly at risk of yellowing.

To protect your resin art from UV-induced yellowing, it's crucial to understand how UV exposure affects the material and take proactive measures to shield it from these harmful rays. By being aware of the impact of UV light on resin, you can implement preventive strategies and preserve the aesthetic integrity of your creations for a longer duration.

Extreme Heat, Moisture, and Oxidation

One of the main reasons resin turns yellow is extreme heat, moisture, and oxidation. These three elements often happen simultaneously and can significantly affect resin projects' appearance.

The Relationship Between Extreme Heat, Moisture, and Oxidation

• When resin gets hot, it can undergo a thermal degradation chemical reaction. This breaks down the polymer chains in the resin, causing it to lose its colour and clarity.
• High temperatures also make it easier for moisture to get into the resin.
• Moisture then speeds up oxidation when resin reacts with oxygen in the air.
• Oxidation breaks down the polymers in the resin even more, causing it to change colour.

Tips for Protecting Resin Projects

To stop yellowing caused by extreme heat, moisture, and oxidation, here are some things you can do:

1. Keep resin projects in a cool and dry place: Don't expose them to high temperatures or humidity.
2. Seal your projects properly: Make sure all edges and surfaces are sealed well so that moisture can't get in quickly.
3. Add a protective top coat: Put on a clear varnish or epoxy resin layer with UV blockers to shield your project from UV light and moisture.
4. Use desiccants or dehumidifiers: These help control humidity levels in your storage area.

Preventative Measures to Avoid Resin Yellowing

Shielding Resin from UV Damage

One effective way to prevent resin yellowing is to shield the resin from harmful UV damage. This can be achieved through UV-resistant coatings, which act as a protective barrier against the yellowing effects of UV light exposure. These coatings contain UV stabilisers, which work at a molecular level to counteract the discolouration effects of UV radiation on resins.

How do UV stabilisers work?

UV stabilisers are compounds added to the coating or resin formulation to absorb or block harmful UV radiation. They function by neutralising free radicals generated when polymers are exposed to UV light, thereby preventing the degradation and discolouration of the resin. By incorporating UV stabilisers into the protective coatings used on resin art pieces, artists can significantly extend the lifespan of their work and maintain its original clarity and colour vibrancy.

Understanding HALS Additives for UV Protection

In addition to using UV-resistant coatings with stabilisers, other preventative measures, such as limiting direct UV exposure, controlling moisture/heat/air exposure, and selecting products with HALS additives, can further enhance the protection against resin yellowing. By understanding and implementing these preventive measures, artists can ensure that their resin art maintains its visual appeal and quality over time.

• Hindered Amine Light Stabilisers (HALS) safeguard resins against UV-induced degradation and yellow discolouration.
• These additives intercept free radicals produced by UV light exposure, thus preventing the chain reaction that leads to resin degradation and yellowing.
• HALS additives are particularly effective in extending the lifespan of outdoor resin applications, such as artworks or coatings, by providing long-term protection against UV radiation.

By understanding the role of HALS additives, resin artists can make informed choices when selecting materials and coatings for their projects, ensuring long-lasting clarity and colour stability in their resin creations.

Other Preventative Measures to Consider

Now that we've discussed the various causes of resin yellowing and the importance of UV-resistant coatings and stabilisers let's explore some additional preventative measures to consider. By implementing these strategies, you can further protect your resin projects from discolouration and maintain their vibrant appearance.

Minimise Direct Sunlight Exposure

One of the primary sources of UV light is sunlight. To prevent resin yellowing, it's crucial to minimise direct sunlight exposure. Keep your resin artwork away from windows, or use curtains and blinds to block out sunlight during the day.

Control Humidity and Temperature Levels

High humidity and extreme temperatures can accelerate the yellowing process in resins. Store your resin projects in a controlled environment with moderate humidity to avoid these issues. Additionally, maintain a stable temperature range between 60-75°F (15-24°C) for optimal resin preservation.

Proper Ventilation in Storage Areas

Adequate ventilation is essential when storing resin pieces to prevent heat and moisture buildup. Ensure your storage area is well-ventilated to allow air circulation, reducing the risk of yellowing caused by trapped heat and moisture.

Remember, preventing resin yellowing is an ongoing process that requires careful consideration of various factors. By combining UV-resistant coatings, UV stabilisers, and these additional preventative measures, you can significantly prolong the lifespan of your resin artwork and keep it looking its best for years to come.

Conclusion

UV light exposure is one of the main culprits behind resin yellowing. Shielding resin from UV damage by using UV-resistant coatings and products with UV stabilisers can help counteract the discolouration effects of UV radiation.

Extreme heat, moisture, and oxidation can also contribute to resin yellowing. Protecting your resin projects from these factors, such as controlling temperature and humidity levels, can help prevent discolouration. Proper handling and storage practices, such as tightly closing resin and hardener bottles to minimise air exposure, are essential in avoiding resin yellowing.