News Letter

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This is Sunjin Beauty Science.

As regulations tighten in the global sunscreen market (EU restrictions on homosalate, the phase-out of oxybenzone and octinoxate, and more), formulating with BEMT(Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine), a next-generation photostable broad-spectrum filter, is no longer optional. It is essential.

But are you struggling because you have been pushing BEMT to 4-5% or more to reach a target of PA 16 (PA++++), only to end up with severe stickiness and an oily, shiny finish that throws your formula out of balance? Forcing in polar oils to dissolve this expensive, poorly soluble filter makes it hard to deliver the light, fresh skin feel that global trends demand from water-based sun serums. The result is reformulating from scratch, with a huge loss of time and cost.

💡Key Result: In a comparison using the same conditions(2.0% BEMT, 3.0% booster), SH305 recorded the highest SPF and PA in both in-vitro and in-vivo testing versus three commercial UV boosters. In the BEMT era, the booster is SH305.

Avobenzone-Era Boosters: Do They Still Work in the BEMT Era?

Widely used photostabilizer-type boosters work by suppressing the photodegradation of avobenzone. This approach is clearly effective in formulas containing photounstable filters. BEMT, however, is inherently photostable. With no photodegradation to prevent, the boosting effect that relied on photostabilization has no role to play.

In other words, the performance of avobenzone-era boosters depended on the presence of a photounstable filter. In the BEMT era, that condition disappears, which is why a booster that works on a different principle is needed.

[Sunjin's Key Solution] The Booster for the BEMT Era: SH305

SH305 takes a different approach. Rather than stabilizing a specific filter, it changes the path of the light itself.
SH305 is a 2 μm bead made from 100% pure silica. Its dimpled surface structure scatters light within the UV film on the skin, extending the light pathway (Extended Light Pathway) so that the UV filters in your formula absorb more light. This is boosting based on a physical principle, regardless of filter type.

Benefit 1: Head-to-Head in BEMT Formulas, #1 in Both SPF and PA

In an O/W formula with 2.0% BEMT and 3.0% of each UV booster, we compared SH305 with three commercial UV boosters: Butyloctyl Salicylate, Ethylhexyl Methoxycrylene, and Acrylates Copolymer.

In-vitro, the SH305 formula showed the best SPF/PA performance. In-vivo, the SH305 formula also recorded the highest performance of the group (SPF 31, PA 15.6).

With the photostability variable removed, SH305 raised both SPF and PA. This shows that SH305 is not merely an auxiliary for a particular filter, but a functional material that contributes directly to UV protection.

Benefit 2: 3% Is Enough

The recommended use level of SH305 is 3%. In an organic-filter-based Airy Sun Serum formula, adding 3% SH305 raised in-vitro SPF from 25.55 to 67.52, with gains leveling off above 3%. Similar results were seen in inorganic-filter formulas.

Benefit 3: In Mineral Formulas, It Replaces TiO2 Dispersion

In a W/O mineral formula, 3% SH305 replaced 7% TiO2 dispersion while maintaining equivalent in-vivo SPF (7% TiO2: SPF 54.2 vs. 3% SH305: SPF 53.5). With less TiO2, white cast is reduced and a transparent skin feel is preserved.

🔎 Summary FAQ: SH305

■ Q1. How does SH305 increase SPF?
SH305 is a 2 μm pure silica bead. Its dimpled surface scatters light within the UV film and extends the light pathway. This lets the UV filters in the formula absorb more light, improving both SPF and PA.

■ Q2. How is it different from conventional photostabilizer-type boosters?
Photostabilizer-type boosters work in formulas containing photounstable filters (e.g., avobenzone). SH305 works through the physical principle of light scattering, so it boosts performance regardless of filter combination. It has also shown superior performance to commercial boosters in photostable, BEMT-based formulas.

■ Q3. What is the recommended use level?
We recommend 3%. In both organic and inorganic systems, gains tend to level off above 3%. Disperse it in the water phase or add it in the post-addition (cool-down) stage.

🚀 In the BEMT era, Sunjin already has the answer. SUNSIL-S45 for formula design, SH305 for boosting. Be the first to prepare your global-market BEMT hit formula with Sunjin Beauty Science.