Writing in its international patent, Unilever said the leave-on composition combined vitamin C in sodium ascorbyl phosphate form with a mineral extract made from olivine that worked synergistically to improve skin tone, skin brightness and mask visible signs of ageing like wrinkles. The formula could be manufactured into a liquid, lotion, cream, foam or stick form but was ideally offered as a serum or essence, the company said.
“The present invention relates to a topical composition that provides energising glow to skin. It more particularly relates to a personal care composition for topical application that delivers a fresh, young and lively look to skin,” Unilever wrote in its patent filing.
Low cost, stable and efficacious
Whilst there were already many topical skin care products on the market designed to tackle blotches, hyperpigmentation, wrinkles or visible signs of acne, many products on the market remained expensive and sat in the premium end of the market. The same could be said for available and proven actives, Unilever said.
An olivine extract developed by Gattefosse, for example, which featured trace magnesium from the olivine stone, had been shown to boost cell metabolism and reduce the effects of skin stressors by increasing adenosine triphosphate (ATP) levels and reducing intracellular oxidation. However, the active ingredient was expensive and when used at levels to improve skin glow developed an “undesirable green colour over time”.
Unilever researchers therefore investigated using olivine in a blend. “After using several actives suggested in the literature, they found that none of them could meet all of the required criteria set by the inventors like low cost, sufficient colour stability, formulation stability, and action standards on the required level of energising brightness,” the company wrote.
Vitamin C ‘surprise’ interaction
“They then found to their surprise that a relatively well known and easily available material which is not known for this benefit viz. vitamin C (which is available in the form of sodium ascorbyl phosphate) interacted synergistically with olivine extract (at low concentrations) to deliver the contrasting requirements of enhanced ATP levels and low colour to the formulation. They also found that vitamin C also boosts ATP levels which is a finding, to the knowledge of the present inventors, not known heretofore.”
Unilever said the reason behind this “synergistic interaction” was “not fully understood” but there were plausible theories.
Scientific understanding, the company said, would suggest it had something to do with vitamin C being an antioxidant and thus offering an important role in reducing oxidative stress – complimentary to the olivine’s magnesium content that stimulated cell metabolic activity. “We hypothesise that vitamin C by its antioxidant mechanism negates the effects of oxidative stress which in turn improves the ATP status of the cells,” Unilever wrote in the filing.
Serum or essence for ‘easy absorption’ and ‘deep penetration’
Unilever said the formulation was ideally offered as a serum or essence because these formats enabled high concentrations and strong skin benefits whilst hydrating and protecting. “Both formats are meant to be used for easy absorption and deep penetration of actives into skin layers.”
Olivine extract was preferably included at 0.1-2% by weight of the composition alongside vitamin C at an inclusion level of 0.05-1.5% total weight of composition.
Unilever said the formulation could also incorporate a skin brightening compound such as lactic acid, vitamin B3 or niacinamide. It could also incorporate colorants, fragrance, exfoliating agents and skin soothing and healing agents.
According to the personal care major, it was also possible to develop wash-off variants of this glow-inducing formulation, such as a cleansing composition in liquid or solid form.
WIPO International Patent No. WO/2023/057266
Published on: April 13, 2023. Filed on: September 28, 2022.
Title: “A topical composition for providing energizing glow on skin”
Inventors: Unilever – A. Damodaran et al.