Rheological Properties of Wool Fat : Role as a Main Ingredient in Skin-Care Cosmetic Products

다국어 초록 (Multilingual Abstract)

The principal objective of the present study has been to systematically investigate the rheological properties of wool fat as a main ingredient of skin-care cosmetic products.
Using a strain-controlled rheometer, the steady shear flow properties of commercially available wool fat were measured over a wide range of shear rates, and the linear viscoelastic properties of the material in small amplitude oscillatory shear flow fields were measured over a broad range of angular frequencies. In addition, the temperature dependency of the linear viscoelastic behavior was investigated over a temperature range most relevant to usual human life. The main findings obtained from this study are summarized as follows : (1) Wool fat exhibits a finite magnitude of yield stress and a marked non-Newtonian shearthinning flow behavior. The appearance of a yield stress and a shear-thinning feature can be explained by the crystalline networks existing within the material. A yield stress is correlated with consistency whereas a shear-thinning viscosity is associated with spreadability.
(2) The linear viscoelastic behavior of wool fat is dominated by an elastic nature rather than a viscous nature. This behavior can be interpreted by the orientation of hydrocarbon chains inside a monodomain. This linear viscoelastic feature could become a criterion to assess the storage stability of cosmetic products at rest or at very small deformations. (3) A modified form of the Cox-Merz rule provides a good ability to predict the relationship between steady shear flow properties (nonlinear behavior) and dynamic viscoelastic properties (linear behavior) for wool fat. (4) The storage modulus and loss modulus show a qualitatively similar tendency to sharply decrease with an increase in temperature. At a temperature range higher than 40°C, both of the two moduli exhibit a more pronounced temperature dependency while the difference between the two moduli becomes smaller.
In the case of the storage modulus, an unexpected plateau region is observed over a temperature range between 25 and 30 °C.

참고문헌 (Reference)

1 Ki-Won Song, "Wall slip of vaseline in steady shear rheometry" 한국유변학회 15 (15): 55-61, 2003

2 B. Medronho, "Viscoelasticity of a Nonionic Lamellar Phase" 23 : 5270-5274, 2007

3 J. D. Ferry, "Viscoelastic Properties of Polymers" John Wiley & Sons 1980

4 A. V. R. Murthy, "The Temperature-dependent Physical State of Polar Lipids and Their Miscibility Impact the Topography and Mechanical Properties of Bilayer Models of the Mil Fat Globule Membrane" 1858 : 2181-2190, 2016

5 S. F. Velick, "The Structure of the Branched Chain Fatty Acids in Wool Fat. An X-Ray Diffraction Study" 69 : 2317-2322, 1947

6 P. Herh, "The Rheology of Pharmaceutical and Cosmetic Semisolids" 30 : 12-14, 1998

7 N. W. Tschoegl, "The Phenomenological Theory of Linear Viscoelastic Behavior" Springer-Verlag 1989

8 U. Hoppe, "The Lanolin Book" Beiersdorf 1999

9 K. W. Song, "Steady Shear Flow and Dynamic Viscoelastic Properties of Semi-solid Food Materials" 11 : 143-152, 1999

10 K. R. Prathyusha, "Shear-thinning and Isotropic-lamellar-columnar Transition in a Model for Living Polymers" 9 : 9983-9990, 2013

11 T. Burns, "Rook’s Textbook of Dermatology" Blackwell Publishing Ltd 2010

12 S. M. Colo, "Rheology and the Texture of Pharmaceutical and Cosmetic Semi-solids" 36 : 26-30, 2004

13 R. Brummer, "Rheology Essentials of Cosmetic and Food Emulsions" Springer-Verlag 2006

14 곽민선, "Rheological investigation of body cream and body lotion in actual application conditions" 한국유변학회 27 (27): 241-251, 2015

15 Eun-Kyoung Park,Ki-Won Song, "Rheological evaluation of petroleum jelly as a base material in ointmentand cream formulations with respect to rubbing onto the human body" 한국유변학회 22 (22): 279-289, 2010

16 T. Moravkova, "Rheological and Textural Properties of Cosmetic Emulsions" 21 : 35200-, 2011

17 R. Brummer, "Rheological Studies to Objectify Sensations Occurring when Cosmetic Emulsions are Applied to the Skin" 152 : 89-94, 1999

18 박은경, "Rheological Evaluation of Petroleum Jelly as a Base Material in Ointment and Cream Formulations: Steady Shear Flow Behavior" 대한약학회 33 (33): 141-150, 2010

19 박은경, "Rheological Evaluation of Petroleum Jelly as a Base Material in Ointment and Cream Formulations : Linear Viscoelastic Behavior" 한국약제학회 41 (41): 161-171, 2011

20 K. W. Lee, "Rheological Assessment of Hand Lotions with Respect to Stability and Application" 12 : 151-154, 2008

21 M. Bekker, "Relating Rheological Measurements to Primary and Secondary Skin Feeling when Mineral-based and Fischer-Tropsch Wax-based Cosmetic Emulsions and Jellies are Applied to the Skin" 35 : 354-361, 2013

22 G. W. Radebaugh, "Phenomenological Viscoelasticity of a Heterogeneous Pharmaceutical Semisolid" 72 : 415-422, 1983

23 J. Zhao, "Phase Behavior and Rheological Properties of the Lamellar Liquid Crystals Formed in Dodecyl Polyoxyethylene Polyoxypropylene Ether/water System" 50 : 641-649, 2011

24 C. Y. D. Lu, "Nonlinear Rheology of Lamellar Liquid Crystals" 25 : 91-101, 2008

25 M. J. Zirwas, "Moisturizer Allergy : Diagnosis and Management" 1 : 38-44, 2008

26 B. A. Macias-Rodriguez, "Linear and Nonlinear Rheological Behavior of Fat Crystal Networks" 58 : 2398-2415, 2017

27 L. Coderch, "Influence of Water in the Lamellar Rearrangement of Internal Wool Lipids" 60 : 89-94, 2007

28 L. Polese, "Extraction and Clean-up Procedure for Analysis of Organochlorine Pesticide Residues in Ethoxylated Lanolin" 55 : 637-640, 2000

29 M. Loden, "Dry Skin and Moisturizers :Chemistry and Function" CRC Press 2005

30 R. Alzaga, "Development of a Novel Supercritical Fluid Extraction Procedure for Lanolin Extraction from Raw Wool" 381 : 39-48, 1999

31 K. Sato, "Crystallization Behavior of Fats and Lipids – A Review" 56 : 2255-2265, 2001

32 C. Yu, "Correlation of Dynamic and Steady Flow Viscosities of Food Materials" 11 : 134-140, 2001

33 A. Sengupta, "Comprehensive View on Chemistry, Manufacturing & Applications of Lanolin Extracted from Wool Pretreatment" 3 : 33-43, 2014

34 E. Jover, "Complete Characterization of Lanolin Steryl Esters by Sub-ambient Pressure Gas Chromatography-mass Spectrometry in the Electron Impact and Chemical Ionization Modes" 970 : 249-258, 2002

35 T. Tadros, "Application of Rheology for Assessment and Prediction of the Long-term Physical Stability of Emulsions" 108 : 143-152, 2004