1 English/German Contents : Editorial 5. Names & News 6. Interview A conversation with Dirk Soontjens, 9. Global Skin Care Market Leader, Dow Corning Technical Articles Freshness without risk 10. Efficient active ingredients for ACH-free antiperspirants and deodorants Greentech Achieving Emolliency and Sensory Effects 12. By Sophisticated Cascading of Volatile Silicone Oligomers By Charles Olsen et al. Grow with the Flow: 18. The Importance of Rheology in Formulating Cosmetic Products By Dr Hemi Nae Cutting-edge Depilatories 26. By Shyam Gupta, PhD. News & Talk A radiant natural treasure 32. Clariant presents Plantasens Abyssinian Oi Clariant Trends & Markets Changing lifestyles drive growth in 35. deodorants By Imogen Matthews Sara Speaks 36. ACNE and Probiotics: The Next Big Thing By Sara Mason New Ingredients 39. New Products 41. Packaging & Machines 42. Events Merck's Dermocosmetics Forum 45.
2 PCHI 2015 45. in-cosmetics Asia 2014 46. Advertiser's Index 47. Market-Place 48. Impressum 47. THE INTERNATIONAL. Dermocosmetic Forum, March 4-5, 2015 MAGAZINE FOR COSMETICS. Merck KGaA AND FRAGRANCES. Frankfurter Stra e 250 64293 Darmstadt Deutschland Tel.: +49 (0) 6151 72-6899 Fax: +49 (0) 6151 72-916899 November/December 2014. 22. JAHRGANG / VOLUME NO. 22. Achieving Emolliency and Sensory Effects By Sophisticated Cascading of Volatile Silicone Oligomers By Charles Olsen*, Gregoire Amice** and Tow Kuan Lem**. accumulation in the environment 1) Subsequent intensive scientific Introduction efforts have helped reduce these concerns. As a result the cosmetic The use of volatile ingredients, particularly in skin care products review boards of both the North America and European Union have can provide significant benefit to consumers of these products. In come to a common conclusion: this article we touch on the regulatory and health information about volatile cosmetic components, compare volatile silicones to volatile O The CIR ( Cosmetics Ingredients Review) board stated that all organics and illustrate the use of volatile silicone materials in skin- of the cyclosiloxanes as currently used are acceptable in cosmetic care with a few example formulations.
3 Formulations 2). O The European Union Directorate General for Health and Con- A Complicated Choice sumer Scientific Committee on Consumer Safety (SCCS) came to essentially the same conclusion and The SCCS is of the opinion The use and application of volatile silicones have long been a that cyclomethicone (D4, D5) does not pose a risk for human mainstay of numerous cosmetic and personal care products. In par- health when used in cosmetic products 3). ticular, their use in fragrances, antiperspirants and sunscreens, as well as in many other categories has made them a critical component Due to the nature of the use and application of products in the for which there have not been other suitable substitutes. cosmetic industry, formulators responsibly err on the side of caution In recent times, however, the low molecular weight-, cyclic sili- when choosing ingredients for their products.
4 For example, this has cone, known as D4, has come under scrutiny and questioned as to its led to a trend away from the use of cyclotetrasiloxane D4, with safety. This question has led the industry to investigate and develop cyclopentasiloxane D5, being used in its place based on the premise suitable alternatives which provide the unusual combination of that the higher molecular weight silicone cyclic would be more physical and chemical properties of this material. The purpose of acceptable. As can be seen in Chart 1, however, the evaporation this paper is to offer alternatives to formulators for the responsible, rates of D5 are considerably lower. This poses a problem when a foreseeable use of needed, alternative, volatile ingredients that pro- faster drying sunscreen is needed for instance. Formulators are now vide essential properties in their products. We believe the final turning to the use of low molecular weight siloxanes alone or in health issue assessment of the low molecular weight silicones is not combinations with cyclosiloxanes to enhance and augment the per- yet agreed upon, in spite of the many different studies, regulations formance characteristics of their products.
5 And directives that been published. To this point, this article will not be discussing these studies, or drawing conclusions about them. Rather, our purpose here is to simply address the emerging needs of the industry and propose alternatives if they become necessary. Some Background on the Issues In view of the very nature of their volatility, these types of volatile, cyclic, low molecular weight organosilicones have always endured significant scrutiny for their potential health and environmental effects. In 2008 Health Canada expressed concern over studies showing possible negative health consequences of D4 and its potential for Chart 1 4). * Director of Technology, AB Specialty Silicones ** BRB International, Ittervoort,The Netherlands ** BRB Amochem, Kuala Lumpur, Malaysia 11/12-2014 12 EURO COSMETICS. Through the use of this range of product volatilities, performance relative to increasing volatility can be enhanced.
6 By means of the use of two or more volatile materials with different evaporation rates one can create a continuously changing viscosity profile of the Octamethyltrisiloxane Decamethyltetrasiloxane product during its application. This is especially important for skin care products such as sunscreens and moisturizers. These products can be applied to the skin with low viscosity and low friction thereby providing a thin, uniform protective layer to the skin. As the volatile Dodecamethylpentasiloxane material evaporates the other properties of the formulation take- Vapor over to provide the intended benefits. Solubility Density Viscosity Com- MW pressure Bp (mg/L, (g/cm3, (cst., pound (g/mole) (mmHg, ( K). 25 C) 20 C) 20 C). 25 C). D3 222 The Critical Function: Uniform Film Formation D4 297 with Good Sensory Properties D5 371 D6 445 The volatile ingredients form an essential component of many MM 162 products, especially in skincare and sun protection lotions.
7 They MDM 236 lower surface tension, increase spreading tendency and act as a car- MD2M 384 .06 7 x 10-5 rier for other ingredients which would otherwise be too viscous, MD3M 310 .43 tacky or insoluble in the formulation. Volatile siloxanes can impart Table 1: Properties of volatile siloxanes the smooth spreading and ease of application in lotions and creams Fluid Hvap and can provide a smooth transition in spreadability without leaving (kJ/kg). an undesirable greasy or fatty feel. A combination of volatile silox- Other Considerations Water 2257. anes can provide a sequential evaporation effect. As each oligomer Isopropyl 779. leaves, the sensation on the skin changes which can provide a luxuri- Volatile materials such as alcohols and Ethanol 846. ous feel. The use of three or more emollients with different spread- hydrocarbons can provide a cooling effect D4 175. ing coefficients has been described as cascading emolliency 5).
8 A which is beneficial in some applications. D5 163. similar concept can be applied by utilizing the wide range of evapo- Volatile silicones can achieve rapid evapo- SF1 184. SF2 150. ration rates available in the volatile siloxanes family. By carefully ration while avoiding this potentially SF 192. selecting the concentration and ratio between the volatile ingredi- undesirable, chilling or cooling effect. ents the formulator can adjust the sensory profile over time to The heat of vaporization in Table 2 is Table 2: Heat of vaporization 6). enhance the application and ultimate performance of the product. directly related to the amount of energy Rather than viewing the elimination of D4 as a problem it can be which is extracted from the surface of the skin which is perceived considered an opportunity to explore new ways to enhance the as cooling as the substance is volatilized.
9 As the volatile siloxanes consumer experience. The clever formulator will be able to create evaporate they remove very little heat from the skin, this result, com- unique and differentiated products which will provide real value to bined with the light friction of a manual application process can leave the customer. the skin feeling warm and soothed. Alternatively in a spray applica- tion, the low heat of vaporization makes the application process much The high spreading coefficient and resulting uniform film applica- less unpleasant especially when applied to sun warmed skin. tion can help enhance efficacy and the pleasant application process encourages usage by the consumer. Flash Degrees point Celsius Potential concerns Acetone -20. The formulators tools Ethanol 13. The flash point of volatile silicones is IPA 12. considerably higher than organics with a SF -1. similar evaporation rate.
10 This makes them SF 1 30. inherently safer, especially when used in SF 57. high concentrations in a formulation. For SF 2 87. example, ethanol has an evaporation rate Table 3: Selected flashpoints approximately the same as Andisil SF 1. Hexamethyldisiloxane but ethanol has a flashpoint of 13 C versus the siloxane flash point of 30 C. Table 3 compares the flashpoints of selected organic and sili- Cyclopentasiloxane cone-based volatile ingredients. 11/12-2014 13 EURO COSMETICS. Other volatile materials are offered to the industry and welcomed Suggested formulations by the formulator as a way to increase the number of tools available for formulation 7). The versatility of the family of silicone coupled Clear Sun Mist Formulation S140721-13. with their unique combination of sensory properties continues to Skin Care Issue date: August 6th, 2014. make them valuable components of skincare formulations 8).