Choosing a UVB filter can become a gamble, and the stress is understandable. You may be looking for a high SPF, a good skin feel, and stability of your formula. On top of this, there are ever-changing regulations to keep in mind. Below is a brief, jargon-free overview of the differences between ethylhexyl triazone and octyl methoxycinnamate.

We will discuss their properties, application tips, and limitations. By the end of this post, you will know which UVB filter is better for your formula.

What Do These Two UVB Filters Do?

To start with, here is basic information about both filters. EHT is an oil-soluble filter peaking at 314 nm. OMC is another name for octyl methoxycinnamate. On a label, you can find ethylhexyl methoxycinnamate or octinoxate (OMC). It is a UV filter peaking at 310 nm. Both filters block UVB rays causing sunburns. Neither of them provides actual UVA coverage, so you will have to use a UVA filter in addition to these two.

Which Filter Provides Higher SPF per Percent?

As a rule, EHT is more efficient per percent. It absorbs UVB intensely, so a little of the filter goes a long way. Thus, a higher SPF can be achieved using less filter. OMC is less efficient per gram, but it usually is cheaper, but need to add with higher dosage to achieve the desired SPF...

Which One Remains Stable in Sunlight?

This is where these filters differ. Ethylhexyl triazone is photostable, so its activity remains high in the sunlight. OMC is photodegradable. Under UV irradiation, it transforms into a cis-isomer with lower absorbance. Also, it can affect avobenzone, a UVA filter, decreasing its efficiency.

Which One Is Easier to Formulate?

In this regard, OMC is much easier. Being a liquid, it mixes easily with other ingredients. It can help dissolve some other filters used in your formula. EHT is a white powder requiring polar emollients to remain soluble. Otherwise, crystallisation may occur at low temperatures.

However, it can be used in water-resistant sunscreens successfully. Nonetheless, it should be tested in your final formula.

What Do the Rules Say?

Now let's move to regulatory aspects. According to Annex VI of Regulation (EC) No 1223/2009 in the EU, a maximum concentration for EHT is 5% and 10% for OMC. In the US, according to the OTC monograph, octinoxate (OMC) is allowed up to 7.5%. However, EHT is not included in the monograph and cannot be used in US OTC sunscreens at the moment.

Besides, since 2021, Hawaii has banned the sale of sunscreens containing octinoxate. The review of UV filters by regulatory authorities continues, so avoid such claims as "reef-safe" or "worldwide approved". Instead, look at the latest rules in markets where you want to sell your formula.

Which One Should You Pick?

Choose EHT if you are interested in a high SPF and photostability of your formula and if it is allowed in the market you address.

Otherwise, go with OMC if cost and processability are your priorities. However, some companies combine both filters with others.

Conclusion

Neither filter wins all the time. It all depends on your priorities, budget, and market. Therefore, pay attention to all aspects mentioned above when choosing a filter.

If you also need chemical sourcing, Sarex is a one stop marketplace for highly efficient, innovative fine chemicals and textile chemicals in India.

Contact Sarex today to start your next project.

Polymers rarely perform at their best in raw form. Left unprotected, plastics degrade under sunlight, lose structural integrity over time, and can pose serious fire risks in certain applications. This is where polymer additives step in, transforming ordinary resins into materials fit for demanding, real-world conditions. Sarex works closely with manufacturers to supply additive systems that address these exact challenges, and understanding how each additive category functions can help formulators make smarter sourcing decisions. This guide breaks down three essential additive types: UV stabilisers, anthranilic acid scavengers, and flame retardants, and explains why each plays such a critical role in polymer performance.

Why Polymers Need Protection in the First Place

Every polymer has vulnerabilities baked into its molecular structure. Exposure to heat, oxygen, moisture, and ultraviolet radiation gradually breaks down polymer chains, leading to discolouration, brittleness, and reduced mechanical strength. Fire hazards present a separate but equally serious concern, particularly in construction materials, electrical components, and automotive parts. Additives are formulated specifically to interrupt these degradation pathways before they compromise the finished product.

UV Stabilisers: Shielding Polymers from Sunlight Damage

Ultraviolet light is one of the most aggressive causes of polymer degradation. When UV radiation penetrates a plastic surface, it triggers photo-oxidative reactions that break polymer chains apart, resulting in fading, cracking, and chalking over time. UV stabilisers work by absorbing this harmful radiation and converting it into harmless heat, or by neutralising the free radicals generated during UV exposure.

Common classes include hindered amine light stabilisers (HALS), UV absorbers, and quenchers, each acting at a different stage of the degradation process. Outdoor applications such as agricultural films, automotive exteriors, and outdoor furniture rely heavily on UV stabilisers to maintain appearance and structural performance across years of sun exposure.

Anthranilic Acid Scavengers: A Lesser-Known but Important Additive

While not as widely discussed as UV stabilisers, anthranilic acid derivatives play a specific role in certain polymer systems, particularly where by-products from processing or degradation reactions need to be managed. These scavenger compounds help neutralise unwanted reactive species that form during polymer processing or long-term ageing, preventing them from accelerating further breakdown or affecting colour stability. In specialty formulations where precise control over degradation chemistry matters, this additive class supports cleaner, more predictable performance over the product's lifespan.

Flame Retardants: Reducing Fire Risk in Polymer Applications

Many polymers are inherently flammable due to their carbon-based structure. Flame retardants work by interrupting the combustion process at various stages:

• Forming a protective char layer that shields the underlying material from heat and flame
• Releasing flame-suppressing gases that disrupt the combustion reaction
• Diluting flammable decomposition products to slow the spread of fire

Common flame retardant types include:

• Halogenated flame retardants – effective and widely used, though facing growing environmental scrutiny
• Phosphorus-based flame retardants – offer a favourable balance of performance and environmental profile
• Mineral-based flame retardants – valued for low toxicity, though often requiring higher loading levels

Industries such as construction, electronics, and transportation depend on flame-retardant additives to meet strict safety regulations. Choosing the right system requires balancing:

• Fire performance
• Mechanical properties
• Processability
• Regulatory compliance across different regions

Choosing the Right Additive Combination

In practice, most polymer formulations rely on a combination of additives rather than a single solution. UV stabilisers might be paired with antioxidants for comprehensive weathering protection, while flame retardants are often combined with synergists to boost efficiency without excessive loading. Sarex supports formulators through exactly this stage, helping identify additive combinations that hold up under real production conditions rather than just laboratory testing. Getting this balance right requires both technical knowledge and access to reliable, well-tested additive systems.

Final Thoughts

UV stabilisers, anthranilic acid scavengers, and flame retardants each address distinct vulnerabilities in polymer materials, and understanding their individual mechanisms helps formulators build more durable, safer products. As applications become more demanding, from outdoor infrastructure to fire-sensitive electronics, the right additive strategy becomes a critical part of product design. Sarex brings that expertise to every formulation challenge delivering additive solutions that meet the performance demands of modern automotive manufacturing.