The science
The protection is carried entirely by particulate filters. Zinc oxide, second on the list and surface-treated with triethoxycaprylylsilane, attenuates across UVB and the full UVA range including long UVA, which is the basis of the PA++++ rating; titanium dioxide, placed seventh, absorbs and scatters strongly in UVB and short UVA and adds to the SPF. Both are dispersed in a water-in-silicone emulsion of caprylyl methicone, trisiloxane and dimethicone with polyglyceryl silicone emulsifiers, disteardimonium hectorite as a suspending clay and trimethylsiloxysilicate as a film-former, which is the system that keeps the particles evenly spread and adherent rather than clumped, and which explains the cream's unusual spreadability for its mineral load. The safety question that follows any modern zinc formulation, whether coated particles cross the skin, was addressed by Mohammed and colleagues in a 2019 study in the Journal of Investigative Dermatology, in which volunteers applied zinc oxide nanoparticle sunscreens repeatedly over five days; multiphoton microscopy found the particles confined to the stratum corneum and skin folds, with no penetration into viable epidermis and no cellular toxicity, supporting the safe use of such formulations. The iron oxides that tint the cream absorb across the visible spectrum, and iron-oxide-containing sunscreens have been shown to reduce visible-light-induced pigmentation in darker phototypes, though at the low concentrations implied by their position here the effect is a modest supplement rather than the full shielding of a purpose-built tinted formula.
Niacinamide, placed just after glycerin, has a substantial record for reducing facial redness, hyperpigmentation and sebum with daily use at 2 to 5 percent; the position is consistent with a working concentration, though the brand states none. Madecassoside, bisabolol, adenosine and nonapeptide-1 appear at the end of the list, where their contribution is tolerability rather than a measurable effect. The brand's SPF 50+ and PA++++ ratings were tested by a third-party laboratory in Korea and have not been published in full or replicated independently; the formula carries no water-resistance claim and no study of this specific product exists.
References 1 ShowHide
- Support for the Safe Use of Zinc Oxide Nanoparticle Sunscreens: Lack of Skin Penetration or Cellular Toxicity after Repeated Application in Volunteers — Journal of Investigative Dermatology (2019)