May 22, 2022 11 min read

How to Cure Epoxy Resin with UV Light: A Comprehensive Guide

Developed for aerospace applications, now a household name, here is how to cure epoxy resin for all your artful cravings. 

How to Cure Epoxy Resin with UV Light

Created in the 1940s for military and aerospace purposes and redefined in the 1970s as an artful masterpiece, epoxy resin is a game-changer for artistic designs. Its glimmer and ability to create a crystal-clear, glass-like finish and its versatility in embedding various objects make it a staple for excellent designs. 

Since its reimagination for DIY use, curing epoxy resin has become very important for creatives. If you're looking for a way to cure epoxy resin quickly and efficiently, UV light might be your solution. UV light has become a popular method for curing epoxy resin due to its convenience and speed. UV light can cure epoxy resin in just a few minutes, allowing you to move on to the next step of your project more quickly.

Epoxy resin is a two-part mixture that requires a hardener to cure. On the other hand, UV resin is asingle-part mixturethat cures when exposed to UV light. While both resins can be cured with UV light, the curing process and requirements may vary. Knowing the differences between these resins can help you choose the right curing method for your project.

The Gist

  • UV light is a fast and convenient way to cure epoxy resin.
  • Identifying the differences between epoxy and UV resins is important when using UV light to cure the epoxy resin.
  • Proper preparation and curing techniques are crucial when using UV light to cure epoxy resin.

Epoxy and UV Resins - What Makes Each One Special

In the special world of resins, many different types exist in the market. Two of the most popular ones are epoxy resin and UV resin. Epoxy resin is a synthetic resin that hardens and solidifies when mixed with a hardener. It is known for its quality and durability, making it a popular choice for various applications. On the other hand, UV resin is a non-UV curing resin that hardens when exposed to UV light. It is less durable than epoxy resin and is often used for smaller projects.

Epoxy resin is a two-part epoxy that requires mixing before use. It is a sticky substance that can be used to create a hard, durable surface. Once mixed, it can be poured onto a surface and left to cure for several hours. The curing time hinges on elements like the temperature and humidity of the environment. Epoxy resin can be used on various surfaces, including wood, metal, and plastic.

UV resins, on the other hand, are less durable than epoxy resins. They are often used for smaller projects because they cure quickly when exposed to UV light. UV resins are soft and pliable when they are not cured, making them easy to shape and mold. They are often used for jewelry making and other small crafts.

Epoxy resin is a hard, solid, and durable substance that is ideal for larger projects. It requires mixing before use and can take several hours to cure. On the other hand, UV resin is less durable but cures quickly when exposed to UV light. It is ideal for smaller projects and can be shaped and molded easily.

The Curing Process

Curing epoxy resin with UV light is a fast and efficient process that involves a chemical reaction between the resin and a photoinitiator. The photoinitiator absorbs the UV light and triggers the polymerization of the resin, resulting in a hard, durable, and glossy finish.

The curing time depends on the exposure to UV light, the wavelength of the light, and the type and amount of photoinitiator used. Fast curing can be achieved by using high-intensity UV lamps or by increasing the concentration of the photoinitiator. However, excessive heat can also affect the curing process and lead to cracking or discoloration.

Hardeners or catalysts are often added to the resin to accelerate the chemical reaction and improve the mechanical properties of the cured material. However, following the manufacturer's instructions and mixing the components in the correct proportions is important to ensure smooth curing and complete polymerization.

Moisture, oil, and other chemicals can also interfere with the curing process and affect the adhesion and durability of the cured material. Therefore, it is recommended to clean and dry the surface before applying the resin and to avoid exposing the cured material to harsh environments.

Here is a brief breakdown of the epoxy resin curing process: 

  1. Prepare your workspace: Ensure you work in a clean and well-ventilated area. UV light can harm your eyes and skin, so wear appropriate protective gear, such as UV-blocking safety glasses and gloves.
  2. Mix the epoxy resin:Prepare your epoxy resin mixture according to the manufacturer's instructions. Mix the epoxy and hardener thoroughly to ensure even curing.
  3. Apply the epoxy: Apply the epoxy resin to your project surface using a brush, syringe, or any other suitable method. Make sure the resin is spread evenly and covers the entire surface.
  4. Remove air bubbles: Use a heat gun or a torch to gently pass over the epoxy surface to remove any air bubbles that may have formed during the mixing and application process.
  5. Position under UV light:Place your project under a UV light source immediately after applying the epoxy. UV lamps or LED UV lights are commonly used for this purpose. Make sure the UV light covers the entire epoxy surface evenly.
  6. Cure the epoxy:The curing time will vary depending on the type of UV light source, the light's intensity, and the epoxy layer's thickness. It can take anywhere from a few seconds to a few minutes. Follow the manufacturer's guidelines for the specific epoxy resin you are using.
  7. Inspect for completeness: After the curing time has passed, inspect the epoxy surface to ensure it has fully cured. It should be hard and no longer tacky to the touch.
  8. Post-cure (optional): Some epoxy resins may benefit from a post-curing process to enhance their properties. This involves leaving the cured epoxy under UV light for an extended period to ensure complete cross-linking and maximum hardness.
  9. Clean up: Clean any tools and equipment that came into contact with epoxy resin using the appropriate solvents or cleaning agents.
  10. Dispose of waste:Dispose of any leftover epoxy resin and disposable materials properly, following local regulations for hazardous waste disposal.

The curing process above is general and will vary depending on the manufacturer’s instructions. Always refer to the manufacturer's instructions for the most accurate curing times and guidelines. Additionally, take the necessary safety precautions when working with UV light and epoxy to protect your health.

Benefits of Using UV Light

Using UV light to cure epoxy resin has several benefits. Its first benefit is the speed with which it cues. UV light can cure epoxy resin within a few seconds, which is much faster than other curing methods. This means that you can complete your project quickly and move on to the next one.

Second, UV light curing produces a strong and durable bond. The bond strength of epoxy resin cured with UV light is comparable to other curing methods, if not stronger. This guarantees that your project will be durable and resistant to wear and tear.

Third, UV light curing is a clean and safe process. Unlike other curing methods requiring heat or chemicals, UV light does not produce harmful fumes or byproducts. This makes it a more environmentally friendly option.

UV light curing is a cost-effective solution. While the initial investment in a UV light curing system may be higher, it pays off in the long run. UV light bulbs have a long lifespan and require minimal maintenance. This means you won't have to replace bulbs or spend money on expensive chemicals constantly.

Overall, using UV light to cure epoxy resin is a smart choice. It is fast, strong, clean, safe, and cost-effective. Whether you are a professional or a DIY enthusiast, UV light curing can help you achieve the best results for your project.

The Role of UV Lamps and Flashlights

UV lamps and flashlights play a crucial role in curing epoxy resin. They emit a specific wavelength of UV radiation that reacts with the photoinitiator in the resin, causing it to harden and cure. UV lamps and flashlights are essential when curing epoxy resin indoors or in areas without direct sunlight.

When selecting a UV lamp or flashlight, it's important to consider the wavelength and output of the device. Most UV lamps and flashlights emit UVA radiation, which is the most effective wavelength for curing epoxy resin. However, some devices also emit UVB radiation, harming the skin and eyes.

UV lamps and flashlights also come in various outputs, ranging from a few watts to several hundred watts. The higher the output, the faster the curing time. However, it's important to note that too much UV radiation can cause the resin to overheat and crack.

Nail lamps can also be used to cure epoxy resin, but they are typically less effective than UV lamps or flashlights. Nail lamps are designed to cure nail polish, requiring a lower output of UV radiation than epoxy resin.

Summarily, UV lamps and flashlights are essential tools for curing epoxy resin. When selecting a device, be sure to consider the wavelength and output to ensure the resin cures properly without overheating or cracking.

Application of UV Light in Curing Epoxy Resin

UV light is a popular method for curing epoxy resin. It is an efficient and quick way of curing resin, especially for small resin crafts like keychains, pendants, and bezels. You can use it for various projects, from jewelry making to sealing and adhesive applications.

One of the principal merits of using UV light for curing epoxy resin is that it is a very precise method. You can control curing more easily, especially when working on small resin crafts. UV light is also very effective for curing large areas quickly.

Choosing the right resin type for your project is important when using UV light to cure epoxy resin. Some resins are better suited for UV curing than others, so make sure you choose the right one for your project.

To use UV light for curing epoxy resin, you will need a UV light source. Many different types of UV lights are available, ranging from handheld devices to larger lamps. Make sure you choose a light that is appropriate for the size of your project.

Using UV light to cure epoxy resin is a great option for many types of resin projects. It is fast, efficient, and precise, making it an ideal choice for small resin crafts and larger projects. You can easily achieve great results with the right resin and UV light source.

Preparation and Curing Techniques

Following the right preparation and curing techniques is important to ensure that your epoxy resin cures properly with UV light. Here are some tips to help you get started:

Mixing Ratio

Before mixing the epoxy resin, ensure you have the right mixing ratio. Follow the instructions on the package carefully to ascertain that you combine the resin and hardener in the right proportions. This will help ensure that the resin cures properly.

Thin Layers

When applying the epoxy resin, it is important to apply thin layers. This will help ensure that the resin cures properly and is not tacky. If you apply thick layers, the resin may not cure properly, and you may have an uneven finish.

Air Bubbles

Combine the resin and hardener gradually and carefully to avoid air bubbles in your epoxy resin. You can also use a toothpick or a heat gun to take out any air bubbles that may have formed. This will make certain that your final product looks smooth and professional.

Colorants and Pigments

If you want to add color to your epoxy resin, make sure you use colorants or pigments that are compatible with the resin. Study and execute the instructions carefully to ensure you use the right colorant or pigment.

Curing with UV Light

To cure your epoxy resin with UV light, ensure you have a UV light source that is strong enough to cure the resin. You can use a UV lamp or a UV flashlight. Depending on the UV light source you are working with, you may need different exposure times for your resin to cure completely. 

Set and Cured Resin

Once your epoxy resin has cured, it should be hard to the touch and not tacky. If it is still tacky, it may not have cured properly. You can test the resin by gently pressing your fingernail into the surface. If it leaves a mark, the resin may not be fully cured.

Uncured Resin

If your epoxy resin has not cured properly, you can try curing it again with UV light. Make sure you follow the instructions carefully and use a strong enough UV light source. If the resin still does not cure, you may need to remove it and start over.

Considerations When Using UV Light

When using UV light to cure epoxy resin, you must consider a few factors. The first is the type of resin you are using. Some resins penetrate deeper than others, so that they may need more UV light exposure to cure correctly.

Another consideration is the equipment you are using. You must ensure that your UV light source is strong enough to cure the resin. If you are using a UV resin kit, make sure to follow the manufacturer's instructions carefully.

Exposure time is also an important factor to consider. UV light exposure time can alternate based on the class of resin you are working with and the thickness of the resin layer. You must experiment with different exposure times to find the right one for your project.

Low temperatures can also affect the curing process. If the temperature is too low, the resin may not cure correctly. Make sure to keep the resin and the UV light at a stable temperature to ensure proper curing.

Shelf life is another consideration when using UV light to cure epoxy resin. Some resins have a shorter shelf life than others, and some may be more expensive than others. Consider the price and durability of the resin when making your purchase.

Finally, consider the cured resin's weight, volume, bonds, flexibility, and stability. These factors can impact the quality of your project. By considering these considerations, you can ensure that your epoxy resin project turns out perfectly.

Final Thoughts

Mastering the art of curing epoxy resin with UV light is a valuable skill for both novice and experienced resin artists and craftsmen. This guide has shed light on the intricate process of using UV light to achieve flawless resin creations. 

By following the guidance in this article, you can unlock the full potential of epoxy resin and easily create stunning, durable pieces. Remember that practice makes perfect, and as you gain experience, you'll develop your own techniques and preferences for resin curing.

UV resin curing offers a faster, more efficient, and often safer alternative to traditional curing methods. It is an excellent choice for various projects, from jewelry making to woodworking. Embrace the versatility and precision of UV resin curing, and let your creativity shine through in your epoxy resin creations. 

Frequently Asked Questions

Can you cure the regular resin with UV light?

No, regular resin cannot be cured with UV light. Only some epoxy resin that contains photoinitiators can be cured with UV light. Regular resin requires a different curing process, such as a hardener or catalyst.

How long does it take to cure epoxy resin with UV light?

The curing time for epoxy resin with UV light can vary depending on the layer's thickness and the UV light's strength. Typically, it takes anywhere from a few minutes to a few hours to cure epoxy resin with UV light. Following the manufacturer's instructions for curing time and UV light strength is important.

What does UV light do to epoxy resin?

UV light activates the photoinitiators in epoxy resin, which initiates a chemical reaction that solidifies the resin. The intensity and wavelength of the UV light affect the speed and quality of the curing process. UV light also helps prevent the epoxy resin's yellowing and fading over time.

What is the fastest way to cure UV resin?

The quickest way to cure UV resin is to use a high-powered UV light with the appropriate wavelength for the resin. Following the manufacturer's instructions for curing time and UV light strength is important. Additionally, using a thin resin layer can help speed up the curing process.