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Hallstar claims to have broken new ground in sunscreen formulation

By Simon Pitman

- Last updated on GMT

Related tags Sunscreen Ultraviolet

Specialty chemicals player Hallstar has launched a new photostabilizer at the Suppliers’ Day show in New Jersey to help sunscreen formulators combine two important active ingredients.

Solastay S1 has been developed to outperform existing photostabilizers for sunscreens as well as having the added functionality of being able to photostabilize both Octyl methocycinnamate (OMC) and Avobenzone together in the same formula.

Combining two actives successfully

“This is a crucial development because these two active ingredients are so vital in the sunscreen formulation arena - in fact it's a game change”​ said Hallstar CEO John Paro, speaking to at the Supplier's Day show yesterday.

“This concept of stabilization has never before been achieved at a technical level, so we are claiming a world first with this product launch.”

OMC is used as a UVB filter, while Avobenzone provides UVA protection. Both are effective and inexpensive sunscreen ingredients that have grown in popularity because they are readily available and relatively easy to formulate.

However, when formulators have tried to combine these two ingredients to provide all important broad spectrum UV protection in the same formulation the two actives have proved to be highly unstable together, and consequently almost impossible to combine.

The research and development team at Chicago-based Hallstar say they have overcome this problem by developing a photostabilizer that works in a concentration-related manner.

Test results

This means as little as a 3 percent dose of Solistay will impart as much as 80 percent UVA and 84 percent UVB photostabilization of Avobenzone in the presence of OMC.

The Hallstar development team says they have proved these results using PMMA plates and vitro-skin that have been coated with varying concentrations of the photostabilizer.

The results showed that even with a 2 percent dose of Solastay, it helped to more than double the photostabilization of Avobenzone, while a 6 percent dose helped to achieve total stability.

The ingredient can be used to provide photostability in a wide range of sunscreen products, including high and low UV protection, as well as a range of different product formats, including creams, lotions, sprays and gels.

“The bottom line for formulators is that this product helps in the creation of photostable and therefore more effective sunscreen products that are easy to formulate using the least expensive and most readily available active ingredients,”​ said Paro.

Related topics Formulation & Science

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