Cosmetics & Personal Care

Korean trends continue to influence cosmetic formulations

By Martin Gunson, Business Unit Manager – Personal Care at OQEMA

Martin Gunson, Business Unit Manager – Personal Care at OQEMA, looks at the impact of ‘K-beauty’ on the global beauty

Martin Gunson, Business Unit Manager – Personal Care at OQEMA, looks at the impact of ‘K-beauty’ on the global beauty industry, with a particular focus on the novel rheology that many of these products exhibit.
The fact that South Korea is among the top 10 global beauty markets, with a market value estimated at just over $13 billion in 2017, it is understandable that western brands are exploring the Korean market’s success. Facial skincare accounts for more than half of the total market share, with $6.5 billion in retail sales and a projected 5.8% CAGR over the next five years to reach $7.2 billion by 2020. It’s no surprise that growth is influencing product development in brands closer to home. 
A 2017 Mintel market report indicated that Korean beauty (‘K-beauty’) trends were having a major impact on the global beauty industry by challenging traditional western formulations, and that this trend was set to continue its drift westwards. This is resulting in a demand for novel ingredients that enhance texture, and enable new higher levels of active ingredients to be incorporated into formulations, creating products that challenge our perceptions and ultimately provide an enhanced product experience for the consumer.
Innovation in rheology
Product innovations that drive the Korean and Japanese markets quickly become adopted into European brands. For example, we are now seeing a steady increase in the numbers of finished products and formulations that challenge the limitations of the traditional “go to” rheological additives.  The multifunctional, yet targeted, approach of these new Korean-inspired concepts often calls for higher electrolyte activities than can be obtained with the use of the standard carbomers. The crystal-clear nature of many of the formulations also limits the extent to which gellant gums, such as xanthan and guar can be used.

Our more traditional approach of western formulation is also being challenged by the novel rheology many of these products exhibit. Key brand leaders such as Shiseido, Amore Pacific, Kosé and Pola all play with the rheological characteristics of their newest formulas to create memory gels that flow seamlessly  back to their original form in an “as if by magic” way, or create products that look like a gel yet behave like a liquid that can be sprayed to leave a light enhanced skin feel.  

OQEMA figure 1.png

These effects puzzle and perplex consumers, who are intrigued by them, play with them, and ultimately purchase them. These innovations challenge formulators to be ever more creative in developing new textures and concepts that constantly push the limits of what is possible, all of which create a demand for new raw materials that can deliver these dreams.

The personal care division of OQEMA, Europe’s newest speciality chemicals distribution company, has been monitoring these trends and, by reviewing the ingredient listings of many of the cutting edge Korean skincare products, OQEMA has identified that many of the formulations contain a novel ingredient manufactured by the Japanese chemicals company ADEKA Corporation: PEG-240/HDI Copolymer Bis-Decyltetradedeth-20-Ether.

What is PEG-240/HDI Copolymer Bis-Decyltetradedeth-20-Ether?
In summary, this is a non-ionic urethane polymer, that forms a water gel and can maintain the viscosity of  the product, even in the presence of organic and inorganic salts, to enable thickening and thixotropic effects to the associated formulation. 

As can be seen from the comparative images in Figure 1, PEG- 240/HDI Copolymer Bis-Decyltetradeceth-20-Ether can be used to create a clear non sticky highly elastic gel, where 1% traditional carbomers create gels that are sticky and don’t easily flow back to their orignial form and which entrain significant air in production. In comparison, Xanthan Gum at 2% produces a flowable sticky product that will flow, but the resultant gel is not clear.
OQEMA figure 2.png

PEG- 240/HDI Copolymer Bis-Decyltetradeceth-20-Ether, manufactured by ADEKA Chemicals Japan under the tradename of ADEKA NOL GT-730, contains two hydrophobic sections that are bonded by urethane groups to a hydrophilic PEG backbone. This structure enables the polymer to create a gel structure with water which, once the polymer concentration reaches a point at which micelles start to form. See a diagrammatical representation of the structure in Figure 2.   
How does it work?
The hydrophobic tails of the polymer form micelles in the aqueous system, whilst the hydrophilic centre creates a network or matrix plugging across the aqueous phase linking into other micelles, thus gelling the water to create stable framework (Figure 3). The resultant gel remains solid, but breaks easily, dependant on the level of polymer present, to flow and reform quickly.  This characteristic enables formulators to develop interesting and novel characteristics in the rheology of the end product.
It also reduces the likelihood of air entrainment, a problem often associated with gel manufacture, as any bubbles formed during the manufacturing process are able to easily flow upwards and burst at the surface, which then reforms to create a smooth layer. PEG- 240/HDI Copolymer Bis-Decyltetradeceth-20-Ether can produce gel viscosities of over 100,000mPa with additions of between 1.5-2% solid without adversely affecting this characteristic (Figure 4).
OQEMA figure 3.png

The non-ionic nature of urethane polymer enables higher addition levels of organic and inorganic salts than would be possible with a more traditional carbomer based system. This enables higher inclusion rates of active ingredients to be considered and achieved. 
The matrix structure created by ADEKA NOL GT-730 can also be employed to create simple emulsions by gelling oils to form silky creams without any need to add a surfactant. Up to 10% of oil can be incorporated into an aqueous gel using just 1.5% of solids.  Additionally, the stability of the gel in both high and low pH ranges makes it ideal for use in many Skin-care, Make-up and Hair styling application where both acidic and alkaline properties may be required.
QEMA found that PEG- 240/HDI Copolymer Bis-Decyltetradeceth-20-Ether is most tolerant of surfactants or amphipathic substances having hydrophobic and hydrophilic groups which are delocalized and do not contain a hydrocarbon chain, examples would be Poloxamer, Polyquaternium-6 and PVP. Surfactants containing delocalized groups and hydrocarbon chains can be used up to 5% without significantly disrupting the gel. 
OQEMA figure 4.png

Formulating the customer experience
A number of formulations with novel rheology are already available from OQEMA Ltd. The Personal Care team of OQEMA Europe are on a journey to further evolve and develop the customer experience. We will drive synergies and expertise in our key locations, becoming evermore the key European partner for product innovation and value. 
Martin Gunson, Business Unit Manager – Personal Care at OQEMA Ltd, Winstons House, Carterton, Oxfordshire, OX18 3EZ, UK
T: + 44 (0)1993 843081, E: