the science page
the science
behind so topical.
For the person who wants to understand exactly why this works. Precise enough for a dermatologist. Clear enough for anyone who has ever read an ingredients list.
count in 14 days
pigmentation
moisture
absorption
We are not a brand that asks you to trust us. We are a brand that shows you the evidence. This page contains every study, every data point, and every mechanism behind the so mask, cited by institution and presented without embellishment.
what microcurrent is
your skin already uses electricity
Every cell in your body communicates through electrical signals. Your skin uses them continuously, to regulate the barrier, coordinate repair, and tell fibroblast cells to produce collagen and elastin. These signals are measurable. They weaken with age. And when they weaken, production slows.
The result is familiar. Skin that loses firmness. Lines that form and stay. A surface that does not recover the way it once did. Some of that is hydration. Some is sun exposure. And some of it is a gradual quieting of the signals that tell your skin to keep rebuilding.
what microcurrent does
Microcurrent is a very low-level electrical current that supplements the skin's own bioelectrical signals. What was measured in the so mask is voltage, which is a different quantity from current: nothing in the mask heats the tissue, and there is no power source beyond the pressure of your hands.
Microcurrent stimulates fibroblast activity. In the published literature, that stimulation is associated with increased production of collagen types I, III and IV, and elastin. What our own clinical testing measured is the change in the appearance of the skin that follows. Professional microcurrent facials have been used by aestheticians and clinicians for decades on this basis.
Most at-home microcurrent devices apply current through probes moved methodically across the face in sections, with a conductive gel. The so mask generates microcurrent simultaneously across the entire face, through a self-contained mineral complex that needs no battery, no charging, and no technique.
the technology: MGM-1 and piezoelectricity
what piezoelectric means
Piezoelectric materials generate an electrical charge when compressed. The word comes from the Greek piezein, to press. The principle is used in lighters, medical ultrasound, sonar equipment, and precision instruments. Apply pressure and the material produces electrical output. Release the pressure and it stops.
The minerals in MGM-1, Bismuth Oxychloride, Titanium Dioxide, Sodium Oxide, and Potassium Oxide, function as a piezoelectric complex. When you press the so mask against your face, the pressure activates the minerals and generates a sustained electrical current across the full mask surface and into your skin. The energy comes from your hands. Every time.
the measurement
The Korea Electronics Technology Institute, a government-accredited national laboratory, measured the electrical output of the mask. Report number 2024-0575F, tested August 2024.
Two conditions were tested. Direct force applied to the mask produced 64.8V peak-to-peak. With a non-conducting film between the contact surface and the mask, the output measured 73.6V.
the patent and formal recognition
The MGM-1 technology is protected by Korean Patent No. 10-2491573, titled 'Skin Sheet Containing Piezoelectric Material,' granted January 18, 2023 following Priority Examination, a status reserved for inventions of recognised commercial significance. It survived full technical examination, prior art search, and office action challenge before grant. so topical holds exclusive ANZ rights.
the second technology
Alongside the mineral complex, the so mask carries NCM: micro-spicules of naturally derived silica, drawn from the skeletal structure of freshwater sponges. Under pressure they open temporary microchannels in the surface of the skin, gently exfoliating and giving what follows a route in.
Our evidence for this mechanism is the supplier's technical documentation rather than an independent study, which is weaker than everything else on this page, and we would rather say so than leave the technology out.
the three mechanisms
collagen activation
The sustained electrical field from MGM-1 supplements the skin's weakening bioelectrical signals. In the published literature, fibroblast cells stimulated by a current of this kind show increased production of collagen types I, III and IV, and elastin. With consistent use the change is measurable, and it is not the temporary surface plumping that a hydrating mask gives you.
Wrinkle measurements were taken using Antera 3D CS by Miravex, a medical-grade 3D imaging device that maps the precise topography of the skin surface using multi-directional lighting. Nine wrinkle parameters were measured. Eight improved significantly.
Protocol note: these results were achieved under a twice-daily application protocol over 14 days. The so mask is designed for 2 to 4 uses per week. The data reflects the capability of the technology under intensive conditions.
deeper ingredient delivery
The current temporarily and reversibly increases the permeability of the skin's outer barrier, a process called electroporation. The effect reverses within 15 to 30 minutes of the current ceasing, which is why the post-mask step is not optional.
The study measured absorption across the stratum corneum, the epidermis and dermis, and the dermal reservoir.
Control patch, without the piezoelectric complex: 32.5 micrograms of niacinamide absorbed in total. Piezoelectric mask: 110.1 micrograms. That is 3.4 times as much overall, and the piezoelectric mask absorbed more in each of the three layers measured, with the largest difference at the surface.
guided actives
Charged molecules move more efficiently in the presence of an electrical field. The so mask contains two that respond to this: Sodium Hyaluronate and Copper Tripeptide-1. The field makes the barrier more receptive and actively moves these through it.
the hydration result
Hydration was measured using a Corneometer CM825, a clinical instrument that measures moisture content in the stratum corneum via capacitance. Readings were taken at three timepoints: before application, immediately after, and 100 hours after. Moisture was measured on a designated forearm site, which is standard practice for corneometry because it controls for the variables a face introduces.
The primary driver of the sustained result is Tremella Fuciformis (Snow Mushroom) Extract, which holds up to 500 times its weight in water. Its smaller particle size lets it sit deeper in the skin than conventional hyaluronic acid, and the current increases how much of it the skin takes up.
the pigmentation result
Pigmentation was measured using a Spectrophotometer CM26dG by Minolta, which measures skin reflectance in the CIE Lab colour space. Across melasma, freckles and blemishes, the measured change after two weeks of twice-daily use was 21.21%, at p=0.000.
Niacinamide interrupts melanosome transfer, the process by which pigment cells pass melanin to surface cells. Combined with the mild tyrosinase inhibition from Ascorbic Acid and Eggplant Extract, this works on the appearance of uneven tone. Independent purity testing confirmed niacinamide in the formula at 118% of specification.
safety and purity
Two independent safety studies. Tested to the standard applied to medical devices. Zero adverse reactions.
Oct 2024
Feb 2026
Sixty participants across two continents. Two regulatory frameworks. Ages 19 to 75, every skin type. Not one adverse reaction recorded at any reading point.
purity testing
Independent laboratory testing by Soonchunhyang University Industry Academy, October 2024.
- Lead, arsenic, mercury, antimony, cadmium, nickelNot detected
- Methanol, dioxane, formaldehyde, phthalatesNot detected
- All parabens (six tested)Not detected
- Total aerobic microbial countLess than 10 CFU/g. Permitted limit is 1000 CFU/g
- E. coli, Pseudomonas aeruginosa, Staphylococcus aureusNot detected
- NiacinamideConfirmed at 118% of specification
- AdenosineConfirmed at 96.5% of specification