For skin care, cosmetic creams are indispensable to many people worldwide. Above all, they provide protection against environmental influences, nourish the skin with moisturizing and revitalizing ingredients, and slow down the process of aging. In addition, there are many special products, such as creams for protection against UV rays or to combat acne or for the prevention of pressure ulcers. Therefore, the cosmetic creams have gained great economic importance. Worldwide sales after selling prices reached €92 bn comparable to the sale of detergents and cleaners (€100 bn, 2018). The increasing cream market accounts for about 25–30% of the total cosmetics market. The undisputed world leader is L'Oréal (France).

The field of cosmetics is exciting, diverse, and spans numerous fields of knowledge that requires teamwork. During the work at HENKEL, my idea to develop highly effective creams in the form of mini (nano) emulsions should expand the existing product range with a line for pharmacy sales. With this task, I started my work in cosmetics. I took over the product and process development and at the beginning the project management (later handed over to the marketing). The project members included a physician, a toxicologist, a researcher, a member of the analytical laboratory, and one person of the dermatological test group to determine the effect of cosmetics. Later, a pharmacist and a marketing member joined the project group. Over the years, as a Doctor of Chemistry with an education in chemical engineering and many years of industrial experience as well as due to close contact with the project members, I have learned a lot from the other fields of knowledge. Furthermore, I was able to contribute my knowledge about hygienic production, Good Manufacturing Practice (GMP) and European Hygienic Engineering and Design Group (EHEDG), from the field of biotechnological production (enzymes). After retiring, I helped a start‐up company for a few years and created the recipes for cosmeceuticals and safety assessments.

With this book, I would like to pass on my knowledge to younger people. The wealth of knowledge allowed me to look at “cosmetic creams” from all angles, including the markets, pricing of products, macro‐ and mini‐emulsions, ingredients, production processes, their materials, scale‐up and guidelines, the physical and medical measurement methods, customer surveys, as well as the creation of safety assessments according to the European Cosmetics Regulations. Of course, the book focuses on the structure and formulation of a cream as well as the effect of each ingredient. As there are many thousands of ingredients, the discussed selection is largely based on own experiences, i.e. proven effects.

The reader must not expect that company recipes will be disclosed here. However, the formulations discussed are partly similar. However, all the described recipes represent free inventions and were neither manufactured nor tested for stability, approval, and toxicology. They should give suggestions for own developments based on natural substances. All formulations have in common that they contain sorbic acid as the preservative (FDA: Generally Recognized As Safe, GRAS) with a pH buffer from citric/citrate, the best tolerated preservative. All information is based on the best of knowledge and belief at the time of writing.

Acknowledgments

For positive contributions, I thank the former members of the working group “Nanoemulsions” at HENKEL, in particular Dr. med. Wolfgang Matthies. Gratefully, most of the mentioned industrial companies have provided images of their machines, apparatuses, and devices. A colleague, Ovid Dicoi, carried out some nuclear magnetic resonance (NMR) measurements and evaluations, integrated in the book (Figures 4.7–4.11). Professor Dr. Dr. h.c. mult. Bernhard Blümich, RWTH Aachen, provided the measuring devices.

My wife supported the two‐year book project with great tolerance and patience.

Thanks to all.

The content of this book is based on several articles, which were mostly published in German.

1. Rähse, W. and Dicoi, O. (2009). Produktdesign disperser Stoffe: Emulsionen für die kosmetische Industrie. Chem. Ing. Tech. 81 (9): 1369–1383.
2. Rähse, W. and Dicoi, O. (2010). Produktdesign von Flüssigkeiten: Parfümöle in der Konsumgüterindustrie. Chem. Ing. Tech. 82 (5): 583–599.
3. Rähse, W. (2011). Produktdesign von Cosmeceuticals am Beispiel der Hautcreme. Chem. Ing. Tech. 83 (10): 1651–1662.
4. Rähse, W. (2012). Enzyme für Waschmittel. Chem. Ing. Tech. 84 (12): 2152–2163.
5. Rähse, W. (2013). Design of skin care products, Chap. 10. In: Product Design and Engineering, vol. 3 (eds. U. Bröckel, W. Meier and G. Wagner), 273–313. Weinheim: Wiley‐VCH.
6. Rähse, W. (2014). Production of tailor‐made enzymes for detergents. ChemBioEng Reviews 1 (1): 27–39.
7. Rähse, W. (2014). Industrial Design of Solids and Liquids, A Practical Guide. Weinheim: Wiley‐VCH.
8. Rähse, W. (2014). Industrial product design: materials for the machinery. ChemBioEng Reviews 1 (3): 117–132.
9. Rähse, W. (2014). Praktische Hinweise zur Wahl des Werkstoffs von Maschinen und Apparaten. Chem. Ing. Tech. 86 (8): 1163–1179.
10. Rähse, W. (2017). Ermittlung eines kompetitiven Marktpreises für neue Produkte über die Herstellkosten. Chem. Ing. Tech. 89 (9): 1142–1158.
11. Rähse, W. (2018). Ökonomische Grundlagen der technischen Reaktionsführung. In: Handbuch Chemische Reaktoren. Springer Reference Naturwissenschaften (ed. W. Reschetilowski). Berlin, Heidelberg: Springer Spektrum.