Colloid & Surface Phenomena Moisturizing Lotion

1. Colloid & Surface Phenomena Moisturizing Lotion Jason Ashbery Jonathan Danner Haohao Huang Leigh Vorreuter

2. I. Product Design Considerations • Customer Needs • Heals dry skin • Prevents dry skin • Non-greasy • Fast absorbing • Non-irritating • Non-scented or Scented • Contains sun screen • Prevent further aging of the skin • Long lasting

3. Product Design Considerations • Different Types of Lotion • For Dry Skin • For Extra Dry Skin • For Sensitive Skin • Manufacturers • Bath & Body Works • Suave • Keri • Bristol Meyer Squibb • Clairol

4. Product Design Considerations • Product Specifications • Shelf life • Duration • Consistency • Viscous properties • Fragrance • Color • Absorption • Delivery systems of alpha hydroxide, sunscreen, moisturizing agents

5. Components and Composition

7. III. Colloids and Surface Interactions • Functions of colloids in Moisturizing Lotion • Diluent • Humectant • Smoothing aid • Emollient • Surfactant

9. Liquid/ Liquid Emulsion • An emulsion is formed when a mixture of two immiscible liquids are separated by a surfactant molecule. • Oil-in-Water (O/W) • Water-in-Oil (W/O)

10. O/W and W/O Emulsion

11. Phase Inversion of Emulsion • Inversion from W/O to O/W • Variables which lead to phase inversion • Temperature – Ethoxylate emulsifiers • Surfactant composition – Hydrophilic emulsifier concentration • Water concentration – Andrew Jergens Co.

12. Effect of Amphiphiles on Delivery to the Skin • Cationic Surfactants • Effect of Temperature and Salt on micelle stability • Effect of Temperature on delivery • Pemulen® Polymeric emulsifiers • Triggered release mechanism upon contact with electrical charge of skin

13. Traditional Surfactant Emulsion

14. Pemulen ® Polymeric Emulsifiers

15. IV. Product Attributes • Shelf Life • Emulsion stability is what determines the product’s shelf like • If the emulsion becomes unstable the lotion will separate • Adjusting the hyrophilic and lipophile balance of the emulsifier achieves the emulsions stability • The emulsions are thermodynamically unstable due to its positive interfacial energy • When the emulsion tries to reach it thermodynamic equilibrium it causes the emulsion to break up back to its component phase

16. Product Attributes • Shelf Life • The delay of the component break up can be accomplished by adding specific mixed emulsions compiled of non-ionic and ionic surfactants and combined with fatty amphiphiles • Examples can be found in Table 3 • Previously blended emulsifying wax into the the formulation can also help prevent the decay of the emulsions • Examples can be found in Table 4

17. Product Attributes

18. Product Attributes • Shelf Life • The gel network theory of emulsion stability is why both emulsifiers and mixed wax help the shelf life period • The emulsifiers stabilize the oil droplets by the formation of an interfacial film

19. Product Attributes • Consistency • It is related to swelling properties and concentration of the α-crystalline gel phase • When the α-crystalline form is in presence of very small quantities of ionic surfactants and a fatty aclohol and is dispersed in water the amount of swelling increases • This leads to the swelling of the α-crystalline gel phase • The water is in between the bilayers of the gel phase and when it swells the volume ratio of dispersed phase to the free continuous phase water increases

20. Product Attributes • Evaporation and Absorption • When lotion is rubbed into the skin water evaporates and the oil droplets coalesce • Coalescence occurs when the interfacial energy between substrates and adatoms is small • The clusters can detach themselves from any given location on the surface and diffuse as entities over the surface • The clusters behave more like liquid than solid crystallites

21. Product Attributes • Evaporation and Absorption • After the application of the lotion the composition changes as the water and other other volatiles solvents evaporate • A film stays on the skin as a protector and the nutrients are absorbed • Absorption capacity increases with decreasing viscosity

22. Product Attributes • Viscosity • Emulsion size and concentration determines the viscous properties • At the same shear stress and droplet concentrations the viscosity of concentrated emulsions containing smaller droplets was significantly greater • This suggests that electrostatic repulsion plays an important role in determining the rheology of concentrated emulsions

23. Product Attributes • Viscosity • The droplets become closely packed causing the emulsions to be come rigid at lower concentrations for smaller droplets because of their effective volume fraction is greater • This explains why low emulsifier concentrations are good for structured lotions • Lotions are not suppose to be very thick and viscous

24. Product Attributes • Fragrance • Fragrances are applied by collodial systems like emulsions • The lipid part of the stratum corneum is organized in lamellar structures • The lamellar liquid crystals in lotions contain the fragrance molecules • The similarity of the configuration of the crystals in lotion compared to the stratum corneum is why it easy for the fragrance to be absorbed into the skin • The location of the interlayer spacings and the geometrical characteristics play a big role on where the location of the fragrance is

25. Product Attributes • Improvements made to the skin • Liposomes have positive effects on the appearance of the skin • Improve cutaneous hydration, skin structure, depths of wrinkles • Liposomes are spherical vesicles that have an aqueous cavity at their center • They are used to carry water-soluble molecules and hydrophobic molecules • Liposomes have been evaluated as delivery systems for drugs, vitamins and cosmetic materials

26. Product Attributes • Delivery Systems • Particulate systems are very small particles that range from micrometers to millimeter • These particles deliver essential active ingredients such as amino acids, plant extracts, minerals, vitamins, antioxidants, and UV protectants • They also prolong the time during which the ingredient remains on the skin

27. V. The effluence of structure of moisturizing lotion (texture parameter) on its use properties, and control of its physical properties

28. Table 1. Texture profile

29. Table 2. Texture profile parameter used in the skin care product evaluation

30. Table 2

31. Table 2

32. 1. Factors influencing the lotion physical parameter • (1). THE EMULSIFIER The emulsifier is the most important role in the emulsion in producing the characteristic flow properties.

33. (2) THE DISPERSE PHASE • There are many parameters related to the disperse phase or internal phase that exert rheological changes in emulsions, including: nature of the oil; viscosity of the oil; particle size; particle size distribution; and particle shape. Particle size and particle size distribution also depend on the emulsifier concentration.

34. (3) THE CONTINUOUS PHASE • The rheological behavior of a lotion is most often determined by the rheology of the continuous phase.

35. (4) PHASE VOLUME RATIO • Generally, it has been found that the rheological parameters of an emulsion increase with creaseing the phase volume ratio.

36. 2. The effects on the behavior of lotion during lotion processing • (1) Mixing • (2) Heating and Cooling • (3)Homogenizing

37. (1) Mixing • Mixing is necessary to blend a water phase and oil phase into an lotion • A high amount of mixing energy can decrease the particle size of the dispersed phase and hence affecting the emulsion viscosity • lotion may be shear sensitive to some degree and mixing can be used to get the desired product viscosity by properly manipulating the mixing variables

38. (2) Heating and cooling • Heating is generally not a problem in cosmetic processing because the product is usually fluid at elevated temperatures • Cooling is more commonly a problem with cosmetic emulsion because it generally increases product viscosity greatly • Cooling has a more important relationship to final product viscosity because of its effect on crystallite size and dispersion

39. (3) Homogenizing • The cosmetic industry usually resorts to homogenization for dispersing solids and insoluble liquids in a liquid phase and reducing the dispersed particles to a minimum size

40. VI. Manufacturing Process • The objective is to disperse one liquid within another in an extremely fine form to make certain that separation due to settling either does not occur or takes place very slowly. • Does not normally involve any extraction or chemical reaction.

41. A Few Parameters that may influence liquid-liquid emulsion formation • Shear rate • Sufficient stabilizers need to be present to maintain the smallest droplet size produced for long periods of time. • Blend time and standard deviation of circulation time. • These along with many other parameters make it difficult to specify a mixing process based on desired droplet size. Most predictions are based on existing data.

42. Pilot Scale Manufacturing Process (US Patent# 6,017,548)

43. Federal Rules and Regulations • GMP’s – Primary objective is to ensure that manufacturers provide consumers with safe and effective products. • Parts 210 and 211 apply to manufacturing of drugs and finished pharmaceuticals. • Part 210 contains a basic overview and some definitions that are used in Part 211.

44. Part 211 • Gives a description of responsibilities of the quality control unit. • States that proper training procedures must be in place. • Buildings and Facility requirements • Cleaning requirements- Rooms and Equipment • Proper labeling and storage of materials • Batch Records

45. Marketing Considerations • Packaging aesthetics • Fragrance • Color of Lotion • Shelf Location