This is an English translation of a news release in Japanese on November 12.
The Makeup Research Laboratory, Biological Science Research Laboratory, and Analytical Science Research Laboratory of Kao Corporation (President: Michitaka Sawada) have developed a new makeup technology to smoothen nasolabial folds inconspicuously with a simple application.
The results of this research were presented at the 31st IFSCC (International Federation of Societies of Cosmetic Chemists) Congress 2020 Convention in Yokohama (held online, October 21-30, 2020).
Apparent age is dependent on skin conditions, such as the presence of wrinkles, age spots, and deep etched "laugh lines" (nasolabial folds), with the latter known to often cause concerns for females aged 40 years and older. Nasolabial folds are deep as compared to other types of wrinkles around the eyes or on the forehead, with shading emphasized by overhanging sagging skin caused by gravity. Thus, they are considered difficult to cover with foundation or application of a concealer. Kao researchers noted that a nasolabial fold can be diminished by lifting up the sagging cheek with a hand and thus focused on development of makeup technology that immediately makes nasolabial folds inconspicuous by physically elevating sagging cheek skin.
Liquids containing specific polymers form a film as they dry and shrink. Kao examined whether sagging cheeks could be lifted by utilizing such shrinkage characteristics.
Initially, the amount of force required to lift a sagging cheek was determined. Next, the shrinkage rate of a film while drying equivalent to the same amount of force was calculated. Since flexibility of the film when dried is important to prevent it from breaking up, screening for polymers with high rates of shrinkage and skin adhesion to the skin, as well as adequate flexibility was conducted. The shrinkage rate was calculated based on the bend angle generated when the formulation was applied to PET film and allowed to dry. For evaluation of flexibility, dried films applied to PET films were folded onto cylinders with different diameters and the minimum diameter at which the film remained unbroken was assessed.
Those results revealed a unique silicone hydrophobic polymer material that exhibited acceptable shrinkage and flexibility characteristics (Figure 1).
Furthermore, equivalent shrinkage of the material even when applied thinly was considered essential to provide a natural finish on the skin. The shrinkage rate of this polymer was found to be high when dried quickly, thus oil with high volatility was added to complete the model formula.
The model formula was applied to the cheek (above nasolabial fold) and around the mouth (below nasolabial fold) of 12 females in their 40s and 50s. Trained evaluators then compared the extent of conspicuousness of each nasolabial fold before and after application using the "nasolabial fold grades" method*1. The results showed that the noticeability of the nasolabial fold was improved in 11 of the 12 participants (Figure 2).
Next, the change of the deepest site of the nasolabial fold before and after application to bare skin in 11 of the 12 participants*2 was measured using a VECTRA® M3*3. The results showed that nasolabial fold depth after applying was shallower by approximately 1 mm on average.
A makeup technology was developed that reduces the conspicuousness of nasolabial folds by non-invasive application to skin. With this new method, cheek sagging is reduced by shrinkage of a membrane adhered to the skin, resulting in the nasolabial fold becoming shallower by an average of 1 mm. This technology will be applied for development of future makeup products that make nasolabial folds inconspicuous and contribute to meet the desire to look as young as possible.
Kao creates high-value-added products that enrich the lives of consumers around the world. Through its portfolio of over 20 leading brands such as Attack, Bioré, Goldwell, Jergens, John Frieda, Kanebo, Laurier, Merries and Molton Brown, Kao is part of the everyday lives of people in Asia, Oceania, North America and Europe. Combined with its chemical division, which contributes to a wide range of industries, Kao generates about 1,500 billion yen in annual sales. Kao employs about 33,000 people worldwide and has 130 years of history in innovation. Please visit the Kao Group website for updated information.