Simple Guide to UV Inhibitors

Published by Kevin Fischer on

Colors make candles unique and enjoyable.

As long as you’re not using pigment-based colors, you can make almost any color without limiting candle performance.

Similarly, fragrance oils exist in a huge variety too which allow extended creativity. Unfortunately, both ingredients in candle wax can degrade from oxygen and light which is why experienced candle makers will incorporate UV inhibitors to fight against the natural course.

Understanding how every possible ingredient behaves in a candle requires a degree in organic chemistry.

Even then, you’d need a complete list of every ingredient in your dye, wax, and fragrance to build a full picture of what’s going on.

Most companies keep their entire ingredients list secret to maintain a competitive edge – you’re unlikely to ever have an itemized list of every component.

The incomplete picture of ingredients often makes it hard to identify the right corrections when things go wrong.

The good news is that some problems have a relatively straightforward solution.

One of those is fading color or scent performance from light and heat which simply requires UV inhibitors to address. Let’s talk about that.

What Are UV Inhibitors

Dye and fragrance are sensitive to the energy in light, which makes them degrade with more light nearby.

Duh.

UV light accelerates oxidation in candles, which also happens to be the root cause of yellowing in candles with higher vanillin content.

Ultraviolet light contains enough energy in its wavelengths to weaken and destroy raw materials in fragrance and dye too, which degrades it differently than oxidation.

So pretty much, ultraviolet light is the worst enemy of our main candle ingredients.

On top of that, figuring out the best way to hinder the impact of UV is a moving target as each industry evolves over time and the chemical makeups transform.

UV inhibitors protect against degradation from wavelength energy and oxidation caused by light.

The lesser known weapon in this fight is HALS: hindered amine light stabilizer.

Wax manufacturers may include this to fight photo-oxidation (bad light effects) with high level chemistry.

For common candle making, typical UV inhibitors on the market may combat the wavelength energy or the oxidation, depending.

Sometimes they tackle both.

  • UV absorbents collect wavelength energy and transform it into heat instead of letting it damage dyes and fragrance.
  • Antioxidants decelerate the oxidation of dyes, fragrance, and wax through a variety of strategies.

When To Use Them

Strong candle colors don’t require UV inhibitors.

You can live without them for your entire career with plenty of success, regardless of what kind of candles you make or wax you use.

Protecting the color profile helps with providing a consistent product line, but most customer’s won’t notice unless the discoloration significantly alters the appearance in a negative way.

You’ll probably be more interested in their use to prevent scent throw loss from UV degradation.

Color is cosmetic, but your scent throw lives inside the promise you make to your customer with your candles.

When should you use UV inhibitors in your candles?

  • Selling outdoors. If you’re selling candles at a market or any area with high sunlight exposure, UV inhibitors will reinforce your design. Highly recommended.
  • Wholesale to retailers. Unfortunately, fluorescent lights or naturally lit stores where your candles live on a shelf can lead to photo degradation too. Besides adding a UV inhibitor, you can also ask for a location in the store away from direct light.
  • Heavy vanillin content. High vanillin content in fragrance oils turns candles yellow even with potentially limited exposure to UV. The antioxidants in the formula help resist discoloration from vanillin.
  • Well-lit storage. Similar to wholesale retailers, consider adding it if your candles remain in the light for an extended period of time. Some workshops don’t have any good options!

Impact On Candle Design

Everything added to a candle impacts everything added to a candle.

Sometimes for better, such as dyes and (most) fragrance oils.

Other times to detriment, when too much Vybar or fragrance oil ends up in the blend.

The point is that optimizing certain parts of a candle may come at a cost in other areas.

The complicated chemistry involved in building candle wax so it plays well with fragrance and oil means commercial wax already contains some degree of additives in them already.

Usually, they are sufficient for almost any candle design, but not always.

UV inhibitors are mostly an exception.

Making sure to follow the suppliers recommendations, many UV inhibitors work without impacting performance or antagonizing other ingredients. Use this if you meet any conditions above, if not just to save some scent strength.

Unfortunately, some people think it helps fight frosting, but that’s just not the case.

If it was that easy to remove frosting, UV inhibitors would be massively popular to support the ever-exploding soy wax market.

Each supplier carries different UV inhibitors, depending on where they buy it from, so check their usage requirements.

If it doesn’t work as you expect in your blend, don’t be afraid to try one from a different supplier!

There are hundreds of different formulations to try, and some are more synergistic than others.

Don’t be discouraged if you’re fighting discoloration or scent loss from ultraviolet light. The answer is a tiny amount of UV inhibitor, so enjoy it as an edge against nature!

Here’s a few on the market:

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