The Delivery Systems' Delivery System

21 The Delivery Systems’ Delivery System James M. Wilmott*, Duncan Aust*, Barbara E. Brockway*, and Vitthal Kulkarni* The Collaborative Group Stony Brook, New York

21.1

Introduction .................................................................................. 438 21.1.1 History of Cosmetics ........................................................ 438 21.1.2 Contemporary Cosmetics ................................................ 438 21.1.3 The Future ....................................................................... 438 21.2 Current Vehicles for Delivery Systems ......................................... 439 21.3 Issues with Emulsions.................................................................. 442 21.3.1 The “Eureka!” Moment ...................................................... 446 21.4 Surfactant-free Lamellar Phase (Lα) Dispersions: An Alternative to the Conventional Emulsification Process ................................. 446 21.5 Defining a Semiquantitative Aesthetic Scale ................................ 450 21.6 Formulating with Lα Dispersions – System 3™ ........................... 452 21.7 System 3™ Advantages ............................................................... 452 21.8 Conclusion .................................................................................... 454 21.9 Formulations ................................................................................. 455 References .......................................................................................... 472

* This work was originally conducted at The Collaborative Group (now owned by Engelhard Corp.). Authors’ present addresses: James M. Wilmott, Chanel Inc., Piscataway, New Jersey Duncan Aust, DPT Research & Development, San Antonio, Texas Barbara E. Brockway, Optima Chemical, London, England Vitthal Kulkarni, DPT Laboratories, Ltd., San Antonio, Texas Meyer R. Rosen (ed.), Delivery System Handbook for Personal Care and Cosmetic Products, 437–472 © 2005 William Andrew, Inc.

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21.1 Introduction 21.1.1 History of Cosmetics Formulating cosmetic and personal care products is an ancient art. These products originally contained ground minerals in an oil or grease. They were initially used by men to exaggerate their features during battle, to conduct tribal ceremonies, and to differentiate different tribes or clans. The use of cosmetics by women began in ancient Egypt. Color products accentuated facial features, plant and animal essences provided a scent to the hair and body, and greases and oils were used to treat the skin. Skin care did not really change over the years and typically involved the application of natural oils or glycerin and rosewater preparations. The first widely used cosmetic dates back to 200 AD when the Greek physician, Galen, published a formula that contained only rose water, beeswax, and olive oil.[1] This formula remained essentially unchanged until the late 1800s when borax was added to the basic formula to form a simple cold cream preparation. The principal cleansing agent at the time was a lyebased soap made by mixing potash or lye with animal or vegetable-based fats. The art of soap making became more refined throughout the second millennium. The era of modern cosmetics emerged in the 1940s with the widespread use of synthetic surfaceactive agents. These materials, commonly called surfactants, modified the surface tension of the oil and water phases and enabled the formulator to mix them together to form a composition that was stable for at least the commercial shelf life of the product. These preparations were called emulsions and the surface-active materials used to form them were called emulsifiers. Personal care products continued to evolve throughout the latter part of the 20th Century. Manufacturers improved aesthetic sensations through the use of new, more refined natural oils and synthetic emollients. Product form became more diverse. Traditionally skin care products were used to treat dryness by plasticizing and softening the hard, rough, tight, scaly manifestations of damaged skin.

21.1.2 Contemporary Cosmetics In the late 1960s and early 1970s functional skin treatment products emerged. Product performance expanded beyond the amelioration of superficial dryness, and their benefits evolved to a higher therapeutic level. The boundary between cosmetics and dermatological products began to blur. Cosmetic problems such as aging, uneven skin pigmentation, slack skin, cellulite, sensitive skin, oily skin, and dryness were identified and agents were sourced or developed to address these conditions. These skin disorders were often associated with conditions such as sunburn, acne, and the need for topical analgesia, etc. Cosmetics turned more to medicine for its resources, and dermatology became a source for agents that could provide either a marketing or performance advantage. As the number and potency of functional materials increased, there arose a need to control the delivery of these agents in order to mitigate potential irritation, target their transfer to the desired location in the skin, or protect environmentally unstable materials for a commercially viable period of time. Again, the personal care market borrowed from the latest advances in medical research. Table 21.1 is a summary of some of the major delivery systems currently being used in the personal care market place, the types of active they carry, and their primary benefit.

21.1.3

The Future

The trend toward even greater performance in personal care products will continue as we move further into the 21st Century. New, more potent therapeutic agents are being sourced from the fields of biotechnology, pharmaceuticals, and botanicals. Materials such as enzymes, growth factors, antioxidants, cytokines, DNA, genetic promoters, and other sophisticated materials are already being evaluated in the research facilities of leading manufacturers and suppliers. These agents, though more effective than previously used actives, are often sensitive to environmental conditions such as oxygen, heat, and light. Thus, there will be a need for equally sophisticated delivery systems that will protect these sensitive actives from their formulation and environmen-

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Table 21.1. Delivery Systems Most Commonly Used in Personal Care

Classification

Description

Diameter

Liposomes

Phospholipid-based unilamellar or multilamellar bilayer vesicles.

100–500 nm

Hydrophilic and hydrophobic actives

Nanodispersions

Phospholipid-based micellular dispersion.

100–500 nm

Hydrophobic actives

Vesicles

Surfactant-based vesicles or micelles

100–500 nm

Typically hydrophobic actives

Polymeric

Crosslinked acrylate or allyl methacrylate polymer

10–500 microns

Typically hydrophobic actives

Microencapsulates

Aldehyde crosslinked protein

100–5000 microns

Typically hydrophobic actives

Encapsulates

Crosslinked guar, alginate, or other carbohydrate polymer

5–500 microns

Typically hydrophobic actives

Entrapment/Clathrate

Clathrate of cyclodextrin

N/A

Hydrophobic actives

Linked

Active ingredient is covalently or ionically linked to polymeric support

N/A

Hydrophilic and hydrophobic actives

tal surroundings. In fact, the cover article of a recent edition of Chemical and Engineering News describes a series of new delivery approaches that have shown early promise in enhancing therapeutic efficacy.[2] While drug delivery systems have received much attention because of their potential, what is often overlooked is the vehicle into which these delivery systems are incorporated. The remainder of this chapter focuses on the proper selection of the vehicle into which the delivery systems are added in order to insure their performance is not compromised. This chapter also explores a new approach to vehicle development that is completely compatible with most, if not all, delivery systems. This new approach is actually a delivery system for delivery systems. The technology employed is more hospitable to the active materials contained within the delivery sys-

Materials Carried

tem. As a result, it offers virtually unlimited aesthetic and form modification capabilities that will enable the user to truly enjoy the experience of applying the product. This new formulating approach is called System 3™. The approach is derived from the very processing technology that was developed to prepare vesicular and liposomal delivery systems.

21.2 Current Vehicles for Delivery Systems The delivery systems most commonly used in cosmetic and personal care products almost universally owe their genesis to the treatment of medical disorders. Tremendous resources are allocated annually in the pursuit of new therapeutic agents. These

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agents are generally administered orally, injected intramuscularly, or injected intravenously with the hope they will eventually migrate to the site where they are needed to treat the disorder. Unfortunately, the lack of specificity of these therapeutic agents often results in unwanted side effects. As a result of this lack of specificity, researchers have initiated the relatively new science of delivery systems technology. The new science is concerned with the development of methods for incorporating the active ingredient into a suitable microvessel or “delivery system,” or chemically attaching the active to a support in order to make a prodrug. The latter approach provides a more stable, chemical modification of the physiologically active ingredient. Either the biochemistry of the skin or the external environment slowly breaks down such modified actives in order to regenerate the active agent. The intention of both of these approaches is the same. They seek to protect the active from a hostile environment, to target the delivery of that active to the site of the disorder, and to control the active’s release properties in order to provide a localized and sustained therapeutic benefit. In almost all cases, the “vehicle” into which the delivery systems are added is water or saline solution. The aesthetic properties of the vehicle are not of consequence in these systems since the therapeutic effect is all that is desired. However, this situation changes abruptly when one uses a delivery system in a product designed for topical administration. Most dermatological products have very limited aesthetic considerations. Typically, the active agent is simply solubilized or dispersed in a standard ointment, salve, or aqueous gel. Standard vehicles, considered pharmaceutically acceptable by the United States or British Pharmacopoeias, are usually selected since the addition of a new active will necessitate a new drug application (NDA) and extensive clinical testing. As a result, many over-the-counter (OTC) drug and dermatological Rx products are aesthetically unexciting. The use of delivery systems in cosmetic and personal care products has an entirely different set of aesthetic requirements. In general, the sensory experience associated with the application of a cosmetic is often the principal reason why a customer might purchase the product. Typical cosmetic vehicles are aqueous-based, anhydrous, or a combination thereof.

Hydrous or aqueous vehicles are principally composed of water that has been thickened to achieve a desired rheological profile. This is usually accomplished by means of the incorporation of a synthetic or natural polymer. Polymers that are most frequently used in the preparation of aqueous-based cosmetic compositions are listed in Table 21.2. These materials impart the desired rheological properties to the product and are designed to take the form of a serum, viscous fluid, or gel. The advantage of these vehicles is they are generally compatible with the delivery system containing the active ingredient. However, the aesthetic properties of such vehicles are very limited and materials that are added to improve the tactile, olfactory, and visible features of the product can be detrimental to the delivery system. Anhydrous vehicles, by definition, contain no water. They have different tactile and rheological properties from aqueous-based systems. Such vehicles take the form of a spray; a very low viscosity fluid or serum; a gel; or a solid, waxed-based stick. These materials are typically composed of hydrocarbons, hydrocarbon esters, natural oils, silicones, or waxes. They have limited aesthetic properties and tend to leave the skin feeling greasy or oily. Such materials are not compatible with many of the current delivery systems. This is particularly true for the vesicular, polymeric, and clathrate systems shown in Table 21.1. The hydrophobic bilayer or micellar character of common vesicular delivery systems tend to simply fuse or dissolve in the hydrophobic character of the anhydrous vehicle. This phenomenon destroys the structure and function of the delivery system and is, therefore, undesirable. Clearly, the preferred cosmetic and personal care vehicle for topical application contains both aqueous and anhydrous phases. Such products have virtually unlimited aesthetic properties and can be applied in many forms such as serums, lotions, and creams. However, these components are generally incompatible with one another unless an agent is added that more significantly reduces the interfacial tension between the oil and the water phases. This phenomenon allows the formation of a two-phase system in which one of the phases (e.g., the oil) is suspended in the other (e.g., the water). Such ingredients are called surface active agents (surfactants). A special subcategory of surfactants is called an

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Table 21.2. Rheological Modifiers

Type

A. Carbohydrate

Thickening Agent 1. Algin

19. Gellan gum

2. Calcium alginate

20. Guar gum

3. Propylene glycol alginate

21. Hydroxypropyl quar

4. Carrageenan

22. Guar hydroxypropyltrimonium chloride

5. Calcium carrageenan

23. Hyaluronic acid

6. Sodium carrageenan

24. Dextran

7. Agar

25. Dextrin

8. Cellulose gum

26. Locust bean gum

9. Carboxymethyl hydroxyethylcellulose

27. Mannan

10. Hydroxyethylcellulose

28. C1-5 aklylgalactomannan

11. Hydroxypropylcellulose

29. Starch

12. Hydroxypropylmethylcellulose 30. Hydroxyethyl starch phosphate 13. Methylcellulose

31. Hydroxyethyl distarch phosphate

14. Ethylcellulose

32. Pectin

15. Chitosan

33. Sclerotium gum

16. Hydroxypropyl chitosan

34. Gum tragacanth

17. Carboxymethyl chitosan

35. Xanthan gum

18. Chitin

B. Polymeric

1. Carbomer

12. Acrylate/acrylamide copolymer

2. Sodium carbomer

13. Acrylate copolymer

3. Acrylate/C10-C30 alkyl acrylate crosspolymer

14. Acrylate/hydroxyester acrylate copolymer

4. Acrylic acid/acrylonitrogen copolymers

15. Acrylate/octylarylamide copolymer

5. Ammonium acrylate/ acrylonitrogen copolymer

16. Acrylate/PVP copolymer

6. Glyceryl polymethacrylate

17. AMP/acrylate copolymer

7. Polyacrylic acid

18. Ethyl ester of PVA/MA copolymer

8. PVM/MA decadiene crosspolymer

19. Isopropyl ester of PVP/MA copolymer

9. Sodium acrylate/vinyl isodecanoate crosspolyer

21. PVP

10. Ethylene acrylic acid copolymer

22. Sodium polyacrylate

11. Ethylene/VA copolymer

(cont’d.)

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Table 21.2. (Cont’d.)

Type

C. Inorganic

Thickening Agent

1. Bentonite

6. Sodium maganesium silicate

2. Quaternium-18 bentonite

7. Lithium magnesium silicate

3. Hectorite

8. Silica

4. Quaternium-18 hectorite

9. Hydrophobic silica

5. Magnesium aluminum silicate

D. Protein/Peptide

1. Albumin

5. Milk protein

2. Gelatin

6. Wheat protein

3. Keratin

7. Soy protein

4. Fish protein

8. Silk protein

emulsifier. These materials not only lower the interfacial tension at the oil/water interface but, with the input of shearing energy, they enable the formation of droplets of one phase within the other. Such emulsifiers have a wide range of surface-active properties. When carefully selected, they can stabilize the incorporation of oil into a water phase or water into an oil phase. The resulting product is called an emulsion. In many cases, such emulsions are prepared by heating the oil and water phases to a temperature of 70°C or greater before combining the two phases. The purpose of heating the phases is to insure that all waxes used are melted, and that the two phases have a low enough viscosity so the two phases can mix freely. The oil and water phases are typically mixed together until they achieve a homogeneous appearance. Thereafter, they are slowly cooled to insure the formation of appropriately smallsized droplets. It is essential that the droplets be very small in order to insure the stability of the emulsion since, in these cases, Brownian motion will retard sedimentation. Such emulsions typically have a homogeneous, opaque, white appearance. They provide a smooth, pleasant feel upon application to the skin, hair, or other epithelial surfaces. In fact, the fields of surfactant chemistry and emulsion science have become a major disciplinary area that a competent cosmetic chemist must master in order to be a successful formulator. The proper use of surfactants to form all of the various types of useful emulsions can become a totally engaging, lifelong pursuit. The vehicle formed by the combination of an aqueous phase with an anhydrous phase is the primary focus of the remainder of this chapter.

21.3 Issues with Emulsions The introduction of surfactants to the cosmetic industry has provided a “double-edged sword” for formulators. Although the many different types of surfactants have yielded a vast array of cosmetics with very desirable aesthetic properties, they have also generated undesirable issues associated with their use. To the formulator, the development of emulsion-based products is replete with problems. Such development is a time consuming process. Further, these issues are generally limiting towards the goal of achieving desirable aesthetic properties. These issues can produce thermodynamically unstable, nonreproducible, and difficult-to-scale emulsions in the manufacturing process. It is easy to understand, therefore, why the time to develop a traditional emulsifier-based product is so lengthy. Seldom does a formulating company’s marketing department or Business Development function request exactly the same formulation. Generally, new marketing concepts will necessitate a change in composition from prior art. This change can cause a cascade of undesirable events. Different aesthetic properties are also frequently requested by Marketing in order to generate new products with new claims. When changes to either the aqueous phase or oil phase are made, the emulsifier blend, which was effective in previous systems, generally must be altered. This may result in a change in one or more aesthetic, performance, or safety properties. Immediate stability of the composition is often compromised as a result and, worse, such instability

WILMOTT, AUST, BROCKWAY, KULKARNI: THE DELIVERY SYSTEMS’ DELIVERY SYSTEM is not usually identified until the second or third month of accelerated stability testing. This behavior may indicate a potential problem with the long-term shelf life of the product, and it is insidious since it requires either rebalancing of the emulsifier ratios or a change in the emulsifiers selected. To be effective in today’s demanding market place, the formulator cannot wait until a potential problem arises in order to address it. Generally, a sequential approach to problem resolution will result in an extended time to develop a product. This will result in a delay in the projected launch date that can cost the organization millions of dollars in anticipated revenues. As a consequence, the formulator is best served by trying to anticipate potential issues. Multiple batches, having several ingredient variations, are typically prepared in order to address any unexpected contingencies. This process is filled with unnecessary redundancy and is generally unacceptable in commercial practice. Compounding the above mentioned issue is the effect that processing can have on the outcome of a batch. Emulsion stability is dependent on a variety of parameters such as the zeta potential, particle size, crystal formation, and water binding activity of the ingredients employed to achieve the desired rheological properties of the product. These parameters are dependent on the temperature to which the oil and water phases are heated, the rate of heating, the method and rate of mixing of the phases when combined at elevated temperatures, and the rate of cooling. Most emulsions require heating to insure that all higher melting point materials, such as waxes and butters, are completely melted, dissolved, or dispersed in the appropriate phase. Some emulsions can be made without heating but these systems preclude the use of higher melting point materials that can add richness to the aesthetics of the final product. Further, if the rate of mixing is high, there is a chance that air can be entrapped in the emulsion. This phenomenon causes an undesirable decrease in the specific gravity of the product and an increase in product viscosity. Any variability in processing can lead to a range of undesirable rheological and textural properties. This issue can occur even if the formulation is not modified! The term “product by process” is well known in the patent art and describes this phenomenon.

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Often, if two or more formulators prepare the same product, the resulting compositions may vary considerably. This surprising variation can occur even though each person utilized the same lots of raw ingredients. The unsettling phenomenon occurs because it may be very difficult to exactly reproduce all of the processing parameters used to make an emulsion. If any of the processing variables is modified unexpectedly the particle size variations may occur or the crystalline properties of the emulsion can be compromised. Table 21.3 is a chart containing the results from an experiment to determine the effect of processing on the final properties of a 5% petrolatum-containing cream. All preparations contained the same lots of ingredients. The data demonstrate that the viscosity and specific gravity can vary dramatically depending upon the processing parameters employed to make the batch. Since there is so much uncertainty at the “bench” level in the laboratory, there is often concern that a typical 500 g to 2000 g lab preparation will not translate directly to a manufacturing environment. This concern is often well founded. Compounding this scale-up problem is the fact that equipment used in the laboratory generally does not correlate with that used in the plant. There is usually a need for an intermediate phase during scale-up that facilitates this transition. Some equipment is engineered to mimic plant conditions but at a fraction of the size. Even so, scale-up issues abound. To deal with the vagaries of scale-up, the product may be subjected to a wide range of processing variations in order to optimize the conditions of manufacture. Products made at each level of scale-up are typically subjected to accelerated stability testing in order to insure the integrity of the product for its anticipated shelf life. When one adds the processing variability and the need for scale-up to the uncertainty of the selection of the emulsifier system, it is almost a wonder that any product ever makes it to the market on time. As a consequence, most formulators tend to stay with the tried and true approaches of the past. A significant alteration to these systems, or the development of an entirely new system is often laced with unknown issues that can severely jeopardize the launch of a new product. Beyond the problems already cited, there are other problems with current emulsifier-based products as well. Some surfactants are not compatible

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Table 21.3. Petrolatum Cream (5%) – Standard Emulsion Test Results

Sample

Specific Gravity

Initial Viscosity (cP)

Viscosity (cP) 24 hr @ 25°C

Viscosity (cP) 24 hr @ 50°C

1. Optimum manufacturing procedure

0.912

99,970

140,580

26,560

2. Overheated phases

0.937

85,910

93,720

29,690

3. Forced cooling

0.952

93,720

109,340

29,700

4. Ambient cooling

0.941

51,550

96,840

131,200

5. Paddle mixing

0.959

62,480

85,910

78,100

6. Rapid homogenization

0.803

112,460

124,960

20,620

7. Underheated phases

0.931

51,550

96,840

20,600

Note: Viscosity measurements were taken with a Brookfield LVT model viscometer. with many of the new ingredients that formulators would like to use. This limits the types of materials and delivery systems that can be used in such products. For example, surfactants destroy liposomes and denature proteins and genes. This situation makes it virtually impossible for cosmetic chemists to take advantage of the new biochemical tools that are proving to be so useful in medical and food applications. Figure 21.1 demonstrates the complete incompatibility of vesicular delivery systems in a standard emulsion vehicle. In this study, phosphatidyl cholinebased liposomes were incorporated into a traditional emulsion prepared using triethanolamine (TEA) stearate and nonionic emulsifiers. The emulsion was then stored at 25°C, and the liposome integrity was monitored by the release of a fluorescent dye from the liposome. What can be readily observed is the rapid deterioration of the liposome in the conventional emulsion vehicle. As seen in Fig. 21.1, the noticeably rapid release of fluorescence in the emulsionbased vehicles demonstrates the well-known and widely publicized fragility of liposomes in the presence of surface-active agents. Similar

undesirable results can be obtained with nanodispersions and vesicular systems as well. Further, it is fairly well established that absorption, entrapment and clathrate delivery systems are also compromised in a surfactant-based system. While the polymeric or cyclodextrin-based structure of such delivery systems is not destroyed, the low surface tension of the aqueous phase promotes a partitioning of the hydrophobic active from the entrapping lattice. As a consequence, the performance agent (i.e., active) is now vulnerable to the environment. In this case, the value of the delivery system for providing control of the amount of active released is irreversibly compromised. This is particularly distressing given the fragility of the new biological and

Figure 21.1 Liposome stability in a conventional emulsion.

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botanical therapeutic agents that are showing so much promise in medical and personal care applications.

to air at high temperature can cause oxidation and lead to both rancidity and an undesirable color change.

As is well known to any first year biochemistry student, oligopeptides, proteins, and nucleic acid polymers are denatured in the presence of surfactants and heat. These are two conditions closely associated with the processing and production of emulsions. Many critically important biochemicals, such as vitamins and organic mercaptans, are susceptible to oxygen, heat, and light. Therefore, if the protection afforded by the encapsulating system is destroyed, then the therapeutic value of the active ingredient is lost.

The complexity of the manufacturing procedure for personal care emulsions, and its dependence on many processing variables, leads to frequent quality issues. This is especially true with respect to the products final textural and rheological properties. If any factors such as the heating, cooling or mixing rates are not carefully duplicated, the material prepared may have different properties than the preceding batches of the same product! As a result, the stability of the emulsion may vary from batch to batch.

Further, many materials with unique aesthetic properties cannot be emulsified easily, if at all. Useful molecular weight silicones, silicone and hydrocarbon-based gels, and fluorinated compounds are all very difficult to incorporate into a stable emulsion system.

Often, the difference of a single parameter is significant enough to cause the product to be outside the established optimum specifications. Inevitably, batches have to be either discarded or reworked. The lack of reproducibility is especially problematic when the product contains a physiologically active agent. Lack of reproducibility, due to manufacturing variations, can affect product performance and decrease consumer satisfaction. It also results in products having undesirable aesthetic properties that the user may perceive as a lack of quality. This will ultimately lead to consumer dissatisfaction, or reduced compliance in product use.

Traditional emulsion systems also create difficulties in manufacturing. The need for heating and cooling systems, specialized high and low-shear mixing, and assorted additional processing devices makes the manufacture of emulsion systems very capital intensive. Further, the equipment specifications and energy requirements will vary from country to country. This situation will cause a modification in the processing variables thereby making it almost impossible to have a truly “global” manufacturing protocol. The energy needed to process such products can be significant and undoubtedly will add to the final cost of the finished unit. This is especially true in Europe and Asia where the price of energy is very expensive. Similarly, there is a long duration of time required to prepare a batch. It can take from 5 to 24 hours, or more, to complete the processing of emulsions depending on the batch size and number of sub-phases required. These concerns minimize manufacturing cacacity, add to the cost, and reduce the gross margin of the final product. The need for high temperature water or steam to heat the phases of the batch can cause damage to heat-sensitive actives such as retinoids and proteins. Prolonged heating of certain materials can accelerate the reaction of the active agent with other components in the emulsion, or with air, if the material is oxygen sensitive. For example, the exposure of unsaturated hydrocarbons, such as vegetable oils,

The presence of a significant amount of surfactant in an emulsion can strip the lipid barrier of the skin. It can also disrupt the lipid bilayer of epithelial cell membranes, thereby leaving the tissue vulnerable. The surfactants themselves may evoke an irritation. Furthermore, the resulting damaged skin barrier then can permit the passage of other materials that can cause irritation, or increase skin sensitivity. Figure 21.2 illustrates the migration of auxiliary emulsion components into the skin. These components include the preservative, chelating agent, fragrance, buffers, and actives. Migration of these components is sufficient to allow penetration deeply enough into the lower layers of the skin and evoke an irritation reaction. The literature is replete with clinical evidence of the damaging consequences that can occur with the use, or overuse, of such surfactants. Effendy and Maibach state that “many surfactants elicit irritant reactions when applied to the skin, partially due to their relative ability to solubilize lipid membranes.”[3] Barany, Lindberg, and Loden

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21.4 Surfactant-free Lamellar Phase (Lα) Dispersions: An Alternative to the Conventional Emulsification Process The current formulation paradigm has considerable vagaries. It is filled with difficulties in manufacturing and a potenFigure 21.2 Penetration of emulsion content into the skin. tially negative impact on the end user in view of compromised performance and irritation. It is, therefore, easy to understand the need claim that “the majority of adverse skin reactions to and desirability of finding an alternative approach to personal care products are presumed to be caused [4] the manufacture and formulation of conventional by substances like surfactants.” In view of their emulsion systems. Ideally, the resulting formulation surface-active nature, surfactants and emulsifiers would have the same, or improved aesthetic propercan alter membrane fluidity, disorganize lipid structies, and would be prepared without the use of traditure, denature both proteins and nucleic acids, distional surfactants and emulsifiers. But where can rupt barrier function, and release inflammatory mesuch a system be found? What means can be emdiators. The results of these actions on the skin can ployed that will allow two immiscible substances to lead to a variety of undesirable conditions; these inmix? The answer to these questions appears to lie clude redness, dryness, scaliness, swelling, and tightmore in the realm of physics than chemistry. Anness. Other conditions that can occur include itchother approach does, indeed, exist. It has been found ing, fissuring, stinging, roughness, and even clinical [5]–[11] that familiar hydrophobic materials (i.e., oils, waxes, conditions such as contact dermatitis. silicones, etc.) can be formed into stable aqueous dispersions via the application of an extraordinary high pressure, high shear process that utilizes unique 21.3.1 The “Eureka!” Moment blends of alkylated phosphatidyl choline (PC). •~ Emulsifier

• Fragrance

n Chelating agent

Interesting things happen when one uses physical methods instead of chemical methods to combine water and oil phases. Stable, surfactant-free dispersions emerge as a new possibility. It all began one day when the simple act of adding a dispersion of a sunscreen to water, thickened with a carrageenan biopolymer, opened a door that gave a glimpse into the future. My team at Collaborative Laboratories and I recognized the virtually unlimited potential of mixing various dispersions together. Having spent over twenty-eight years in developing or managing the creation of countless cosmetic and personal care products, I realized the new approach could resolve almost all of the issues that existed with the preparation of conventional emulsion systems. Further, the technology could be readily transferred to topical drug delivery, nutritional products, veterinary medicine, and even household and industrial applications.

Molecules of phosphatidyl choline and certain other phospholipids will spontaneously form assemblies with one another in water at extremely low concentrations. These assemblies are typically bilayers with the polar head group of the molecule interacting with the external and internal aqueous phases. Concurrently, the nonpolar, aliphatic portion of several molecules interacts with one another or with a non-polar fluid to form the bilayer. Phosphatidyl choline (PC) can form up to eleven different stereochemical assemblies in water depending on the alkyl groups present, the phase transition temperature of the molecule, the concentration of phosphatidyl choline present, the temperature at the time of formation, and the shearing energy applied during formation. Some of these assemblies are more thermodynamically stable than others.

WILMOTT, AUST, BROCKWAY, KULKARNI: THE DELIVERY SYSTEMS’ DELIVERY SYSTEM Typically, assemblies formed above the temperature at which the molecule changes the structural character of the phospholipid (i.e., transition temperature) are more stable because of the lower entropy present. However, assemblies often transition to a less stable assembly as the system is cooled. Blends of phospholipids generally form more stable assemblies probably due to the synergistic packing of the phospholipids. Ideally, if one could introduce energy without the use of heat, then it would be possible to form more stable assemblies. One type of more stable assembly is known as the lamellar phase (Lα). A solution to the above stated problem is the introduction of high energy input at low temperatures. This can be achieved by exposing phospholipids to extremely high shear rates under extreme pressure. Such shear is achieved by having the fluid physically diverted into two channels that impinge upon one another in a chamber at velocities that can approach 500 m/sec. Further, the shearing action resulting from this geometry takes place under extremely high pressures ranging from 10,000 to almost 50,000 psi. Upon exiting the chamber, the fluid expands as it returns to atmospheric pressure, and this causes an ultra-efficient break-up of the hydrophobic material. Under the right combination of shear and pressure, enough energy can be imparted to allow almost instantaneous formation of extremely small droplets of the hydrophobic fluid which are stabilized by the concomitant formation of Lα phospholipid assemblies. Since the formation process is almost instantaneous, the amount of time that the process media needs to be exposed to high shear rates and extremely high pressures can be very short indeed! This time duration is so short, in fact, that the phospholipid assemblies formed do not have time to disassemble before they are no longer exposed to the shear and pressure conditions used to form them. Remarkably, by employing this procedure, lipophilic materials can be successfully incorporated into an otherwise all water-based product. The most important state in which the phospholipid assembly can exist for generating stable oil-inwater dispersions is the fluid lamellar or Lα phase, also known as the liquid crystalline phase. The liquid crystal phase exists as a transition between the solid and liquid states. The existence of this phase is only possible above the gel-to-liquid crystalline transition temperature (i.e., required energy level) of the

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phospholipid or mixture of phospholipids used. The gel-to-liquid crystalline transition temperature is defined by that amount of work input needed to change the structural character of the native phosphatidyl choline molecule that exists as a less stable Lβ phase (also known as a gel phase) to a more stable Lα phase. The Lα phase has two phospholipid assemblies that can form. The first type is the usual unilamellar or multilamellar phospholipid bilayer. This bilayer has large regions of water between the bilayers. Figure 21.3 is an illustration of a unilamellar liposome containing an encapsulated aqueous phase.

Figure 21.3 Liposome bilayer.

The second type of assembly that can form is the result of a conversion that occurs in the presence of relatively large amounts of hydrophobic materials and water. Here, the phospholipids rest at the surface of the hydrophobe droplet. The lipophilic tails of the phospholipids extend into the hydrophobe while the more polar heads of the phospholipids interact with the surrounding water to produce a micelle-like structure. Unlike many emulsions prepared by conventional means, the amount of hydrophobe that can be accommodated into a stable, water miscible dispersion can be greater than fifty percent by weight. Different hydrophobes vary in their ability to be incorporated into the stable Lα phase configuration. Generally, non-polar hydrophobes can be incorporated much more easily than more polar ones. Higher purity hydrophobes will usually be capable of incorporation at higher levels than those of lower purity. Most silicone derivatives can be incorporated at very high levels. Figure 21.4 is an illustration of a

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particle containing a high level of an oil whose surface is stabilized by the presence of phospholipid molecules.

Figure 21.4 Micelle-like phospholipid assembly of an oil.

the distribution of particle sizes for the micelles is extremely narrow. While a small amount of phospholipid is required for the formation of Lα dispersions, the resulting product can clearly be considered to be surfactant-free. The phospholipid molecules contained in the Lα dispersions have the tendency to self assemble into micelles even in the absence of a hydrophobe. This happens even when the concentration of phospholipid is extremely small (less than 10-10 millimolar). As a result of this behavior, the phospholipids produce essentially no irritation when applied to the skin. Further, they do not promote skin barrier damage, but rather promote its repair since phospholipids constitute a critical component of the cellular membrane. Oil dispersions made by the high pressure/high shear process, using these phospholipids, have a surface tension that is essentially the same as water. Figure 21.5 illustrates a comparison of the surface tension of pure water (73 dynes/cm), an Lα dispersion (71 dynes/cm), and a conventional oil-in-water emulsion (25 dynes). Figure 21.6 depicts the contact angle of a droplet of water on skin treated with an Lα dispersion (61°), a cationic emulsion (37°), an anionic emulsion (13°), and a conventional nonionic emulsion (15°). These data suggest that Lα dispersions are truly different than surfactant-based emulsions and, in fact, may be considered surfactant-free.

The critical aspect of the production of stable Lα-phase dispersions is processing at low temperatures and using high-energy input. The process used must exceed the energy level requirements needed for the transition from the gel phase to the liquid crystalline phase without actually heating the system to the transition temperature. The Lα-phase assembly must be formed in a fraction of a second, One of the most interesting aspects of the Lαand the conditions that allowed the assembly to form phase dispersions made by the high shear/high presmust then be removed immediately after the assemsure process is the viscosity of the final dispersion. bly formation is complete. The result of this process is a stable dispersion of highly concentrated hydrophobes that can, thereafter, be freely dispersed in water or water-based products. Typically the particle size of the micellar structures created during the process will be from 100 to 500 nanometers in diameter. This size is about 1/ 10 to 1/50 the size of particles produced by standard emulsification techniques. Further, the use of the high pressure, high shear processing described Figure 21.5 Surface tension of Lα dispersions and a conventional emulsion. above, is so efficient that

WILMOTT, AUST, BROCKWAY, KULKARNI: THE DELIVERY SYSTEMS’ DELIVERY SYSTEM

Lα Dispersion (θ = 60.9°)

Cationic Emulsion (θ = 37.1°)

Anionic Emulsion (θ = 13.0°)

Non-ionic Emulsion (θ = 14.8°)

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Figure 21.6 Contact angle measurements of water on treated skin.

Typically, any stable emulsion containing 25% or higher concentration of petrolatum will have a Brookfield LVT viscosity measuring over 100,000 centipoise. By contrast, a high-shear, high-pressure processed dispersion of 25% petrolatum in water will have a much lower apparent viscosity in the range of less than about four hundred centipoise as recorded by a Brookfield LVT viscometer. As a result of this low viscosity, such dispersions can be readily sprayed by means of a finger-actuated pump sprayer. This astonishing difference is entirely due to the type of dispersions produced by the high shear, high pressure process. A formula containing 50% petrolatum, processed by the described high shear, high pressure process, is a stable, elegant lotion with an apparent Brookfield viscosity of approximately 4,000 centipoise. The exact same formula, made by conventional homogenization, has an initial viscosity of 360,000 centipoise, is extremely inelegant and is not stable at room temperature for more than seven days. Further, the high pressure, high-shear process imparts a negative charge or zeta potential on the

surface of the micelle that repels them from neighboring micelles. Therefore, the hydrophobic micelles are free to move past one another, thereby creating a low-viscosity, fluid environment. High molecular weight polydimethylsiloxanes, having a viscosity of 60,000 centipoise and higher, have an excellent skin feel when incorporated into a topically applied product, but their rubbery texture and chemical composition make them very difficult to successfully emulsify into a cosmetic or pharmaceutical composition. A 30% Lα-phase dispersion of such a high molecular weight dimethicone is a low viscosity liquid that is completely water dispersible! Lα dispersions can sometimes provide a method to incorporate ingredients that do not lend themselves to processing by any conventional emulsification system. For example, it is possible to make stable 30%–50% Lα-phase dispersions of fluorinated materials such as polytetrafluoroethylene and perfluoropolymethylisopropyl ether. These dispersions

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can be further diluted in water, even though neither of these two materials is considered to be easily emulsifiable by conventional means. Lα dispersions can be made with virtually any hydrophobic material by carefully controlling the selection of phospholipids and the processing conditions during manufacture. One interesting property of these dispersions is they can alter the aesthetic properties of virtually all materials. This feature results in the opportunity to create new sensations with familiar materials. Conventional materials such as petrolatum, lanolin, waxes, and natural oils are given a new “life” and purpose. Since the micelles of each hydrophobic material are made the same way, they are all independent of any surfactant, and, because they have approximately the same particle size and negative surface charge, there is no tendency for the micelles to coalesce. High pressure, high shear manufactured dispersions of various low polarity lipophilic agents (lipophiles) mix together readily, without issue. The practice of balancing the hydrophilic and lipophilic emulsifiers (HLB), depending on the composition of the lipophilic phase, that is used so commonly in the preparation of standard emulsion systems is now made obsolete by Lα systems. Thus, a virtually infinite array of lipophilic dispersions can be mixed, in any proportions, without creating any instability in the final blend.

21.5 Defining a Semiquantitative Aesthetic Scale A series of Lα dispersions can be prepared that have a range of aesthetic properties ranging from “very light,” with no residual feel to “very emollient” with a noticeable and prolonged residual feel. This range of properties permits the generation of a spectrum of tactile sensations that can be combined to create virtually any aesthetic experience. An arbitrary aesthetic scale from 1 to 1,000 can be established in order to describe the aesthetic properties of a given dispersion. Those having a light, rapidly absorbing property would be on the low end of the scale. Dispersions having a more unctuous, long-lasting effect, would be designated with a value at the higher end of the scale. Other lipophilic dispersions could then be assigned intermediate values depend-

ing on the degree of tactile properties they demonstrate. For example, a low viscosity, hydrogenated polyisobutene dispersion is assigned the number 100 for its light tactile impression and fleeting after-feel. By contrast, a cetearyl alcohol dispersion is assigned a value of 900 because of its pronounced emolliency and noticeable, prolonged waxy after-feel. Similarly, cylcomethicone, phenyl trimethicone, a higher viscosity hydrogenated polyisobutene, petrolatum, gelled silicone, and gelled hydrogenated polyisobutene have been assigned numbers of 200, 300, 400, 500, 600, and 700, respectively. Recently, dispersions of grape seed oil, cotton seed oil, olive oil, mineral oil, and cocoa butter have been developed. These have been assigned numbers of 250, 450, 650, 750, and 850, respectively. Mixing these dispersions creates a virtually limitless range of tactile properties. Statistically speaking, the mixing of the simple fifteen aesthetic-modifying dispersions described above, can produce fifteen factorial combinations (1.307 × 1012) when the concentration of each active modifier is constant! Table 21.4 is a chart that illustrates the effect of various aesthetic-modifying dispersions on the properties of a final product. When the concentrations are varied, almost limitless numbers of combinations of aesthetic behavior are possible. This effect is analogous to that obtained in the color field, where the blending of three primary colors (red, blue, and yellow) can create virtually any shade of color that exists simply by varying the ratio of each of these primary colors. History shows that, with these three agents, artists have been able to produce countless great masterpieces that possess myriad shades of colors. Lα dispersions of lipophilic performance materials (i.e., actives) can also be readily prepared. These materials provide the finished product with its functionality. Sunscreen agents such as ethylhexyl methoxycinnamate, octacrylene, and homosalate can be incorporated into stable Lα dispersions at levels from 30 to 50 wt%. Similarly, retinoids, vitamin E (α-tocopherol), α-bisabolol, polydimethylsiloxane, essential fatty acids, and petrolatum can be made into stable dispersions in order to provide the finished product with a range of useful properties: these include anti-aging, antioxidant, anti-inflammatory, moisturization, and skin protectant features. Such

WILMOTT, AUST, BROCKWAY, KULKARNI: THE DELIVERY SYSTEMS’ DELIVERY SYSTEM dispersions are completely compatible with the Lα dispersions used to modify the aesthetic properties. Since all of the dispersions discussed thus far are made essentially devoid of traditional surfactant, they offer a powerful new degree of flexibility since they are compatible with the sophisticated delivery systems being created for pharmaceutical and

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personal care applications (Table 21.1). Liposomes, nanospheres, encapsulates, and many other types of delivery systems maintain their integrity when mixed with Lα dispersions. By contrast, emulsifiers and other surfactants rapidly disrupt such systems, which makes them valueless in the formulated product.

Table 21.4. Properties of Aesthetic Modifying Dispersions

Aesthetic Modifier*

Initial Feel

Absorbency/ Playtime

Residual

AM 100

Very light

Short

Low, smooth

AM 200

Very light

Short

AM 300

AM 400

AM 500

Light

Light but with richer texture

Rich

Medium

Medium

Medium

Comments Increases opacity of final product. Oil-free.

Helps to reduce any tackiness in Emollient with finished product. Imparts a matte smooth after-feel finish. Light, silky after-feel

Helps to minimize tackiness in finished product. Provides "dry" emolliency to the end-feel.

Emollient with slight tackiness

Use in products for normal-oily skin. Consider using AM 200 or AM 300 to eliminate any tack. Increases opacity of final product.

Slightly unctuous Tackiness can be reduced with rub in with rich, AM 200 or AM 300. Provides slightly tacky good residual feel. after-feel Emollient, silky after-feel

Good moisture barrier. Ideal for sunscreens and waterproofing. Reduces tack and drag.

AM 600

Elegant texture

Short

AM 700

Rich

Long

Unctuous, slighty Excellent waterproofing agent for tacky emollient sunscreens. after-feel

AM 800

Rich, heavy

Long

Unctuous, waxy after-feel

Tackiness can be reduced with AM 200 or AM 300. Increases viscosity.

Waxy

Increases opacity of final product. Adds body with elegant waxy after-feel. Reduces tackiness.

AM 900

Very rich

Very long

* Asthetic modifiers are oil-in-water dispersions manufactured by Collaborative Laboratories.

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21.6 Formulating with Lα Dispersions – System 3™ The Lα dispersions are freely miscible with water and can be infinitely diluted if desired. The dilution process simply reduces their viscosity. However, if the water is first thickened with a natural or synthetic rheological-modifying agent, then the addition of the Lα dispersions creates a product that looks and feels like traditional emulsion systems. Examples of such rheological modifying agents include: carbohydrate polymers such as xanthan gum or acrylate-based polymers like Carbomer. Depending on the amount of the thickening agent or agents used, the final form of the formulated product can be designed to be a thick cream, a soft cream, a lotion, a serum, or even a low-viscosity fluid. Virtually every aqueous thickening agent is compatible with the Lα dispersions. However, materials such as xanthan gum, methacrylate polymers or copolymers, starches, and silicates that introduce thixotropy (i.e., viscosity decreases with time at constant shear rate), permit the formulation of elegant finished goods. If the final system is to be acidic, or contain significant amounts of acids such as alpha-hydroxy acids, then the use of xanthan gum, sclerotium gum, hydroxethyl cellulose, magnesium aluminum silicate, carrageenan, and modified starches is recommended for use with Lα dispersions. Other potentially useful polymeric thickening materials can be found in Table 21.2. These thickened water phases should contain little, preferably no, surfactant. The presence of surfactant can perturb the stability of the surfactantfree dispersions, or the delivery systems selected for the desired active ingredients. Water soluble performance ingredients such as glycerin, vitamin C, or herbal extracts can be added directly to the thickened aqueous phase. Products can be made that are indistinguishable from standard emulsion systems. More importantly, formulations with unique aesthetic and performance properties can be prepared that enhance the enjoyment of the customer during use. The preparation of surfactant-free formulas requires three components: a thickened water phase, a selection of Lα dispersions to produce the desired aesthetic properties (i.e., System 3™), and an active, or performance material. The active can be present by itself, or incorporated into a delivery system. This combination of materials provides the

final product with its functionality. They may be combined concurrently, or sequentially. Since the particle size of the lipophilic dispersions are already preestablished by the high pressure, high shear processing, they can be simply mixed into the thickened water phase with gentle agitation at room temperature. The rheological properties demonstrated are primarily due to the presence of the thickening agents employed. They are completely independent of the complex processing conditions required to make conventional emulsions. No heat or extraordinary processing conditions are required. More remarkably, these systems are far more stable than their emulsifier-based counterparts. The hydrated thickening agent(s) provide a matrix into which the Lα aesthetic and performance dispersions are embedded. As long as the thickening agent retains its integrity at various temperatures, then the product will maintain its stability. Thus, unlike ordinary emulsions, these dispersions have the potential to be thermodynamically stable indefinitely!

21.7 System 3™ Advantages Surfactant-free formulating has many advantages. The time development, from concept to the market place, is dramatically reduced. There is no longer a need for the preparation of multiple, redundant formulations. Laboratory efficiency can be increased dramatically. Typically, surfactant-free formulations can be prepared in 10–15 minutes. This allows a formulator to prepare 30 or more prototypes daily. This acceleration in speed of formulation variation is amenable to the effective use of statistically designed experiments. The aesthetic and rheological properties of the product can be evaluated immediately. There is no need to wait overnight to determine the properties of the product, as is often the case with standard emulsions. Greater flexibility and rapid formulation changes are possible. Since the products are devoid of traditional surfactants, they are less irritating to the skin. A much wider range of aesthetic product types can be made. The compounding of surfactant-free formulations is a cold process that readily scales to manufacturing conditions. The need for multiple pilot batches to optimize the processing conditions is virtually eliminated.

WILMOTT, AUST, BROCKWAY, KULKARNI: THE DELIVERY SYSTEMS’ DELIVERY SYSTEM Surfactant-free formulations have distinct advantages in manufacturing as well. They are significantly less expensive to produce. The process conditions are uncomplicated. Labor, overhead, and processing time can be reduced from 50% to 75%. This improvement in production efficiency results in plant capacity increases without any additional capital investment. If capital equipment is needed, it will generate savings of about 70%–80% as compared to processing equipment needed for the manufacture of conventional emulsions. Since no heating and cooling is required, energy savings can be greater than 90%. There are fewer materials to compound, and no sub-phases are required. Quality is dramatically improved since it is much easier to insure batch-tobatch reproducibility. There is little waste, and virtually no “rework” of a batch is required. Kettle dwell time is greatly reduced, and the product can be transferred directly to the filling line once ingredient additions are completed. In fact, continuous processing is possible. Finally, the ease of manufacturing enables the product made with Lα dispersions to be made exactly the same in any location in the world. Perhaps most importantly, the consumer benefits from the use of surfactant-free formulations. The Lα-based systems are potentially more efficacious and less irritating. Therefore, they will have much greater consumer appeal. The integrity of liposomes and other delivery systems is maintained since the Lα-based systems are essentially surfactant free. This permits the optimal penetration of the desired physiologically active ingredients, while retarding the penetration of unwanted materials. Further, liposomes are completely compatible with the System 3 vehicle. Figure 21.7 shows the long-term stability of the liposome when stored at elevated temperatures in a System 3 base. System 3 formulations have other interesting properties that enable them to serve as the ideal vehicle for various delivery systems. This capability is the basis for calling Sytem 3 formulations, “The delivery systems’ delivery system.” As stated previously, since no surfactant is present, the System 3 vehicle has a surface tension essentially the same as water (see Fig.

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21.5). When applied to a surface like hair or skin, the lipid barrier of the substrate is not compromised. Penetration of the active is then controlled by the nature of the delivery system and not by the properties of the vehicle. This is extremely important because it allows the formulator to fully describe any beneficial or negative effects solely based on the properties of the contained active, without any confounding effect of the vehicle. The use of System 3 typically provides lower penetration of the vehicle components into the skin and, consequently, irritation potential is reduced as compared to standard emulsion. Because of the low penetration, the uniformity of the resulting layer of product on the skin allows for an even distribution of the active and/or the delivery system at the skin surface. This property is readily confirmed when 20.0% of a nanodispersion containing 37.5% ethylhexyl methoxycinnamate and 10.0% butylmethoxydibenzoylmethane is added to a System 3 vehicle so that the concentration in the final product is 7.5% and 2%, respectively. (See Formulation 21.1 at the end of the chapter.) The sun protection factor (SPF) performance of this formula is compared with a conventional surfactant-based emulsion containing the same level of sunscreen in Fig. 21.5. It can be seen that there is essentially a doubling of the SPF value when the System 3 vehicle is employed. Another added advantage observed is that the System 3 formula is essentially waterproof, whereas the conventional emulsion vehicle is not. In fact, the conventional emulsion vehicle would require the addition of supplemental waterproofing agents to achieve this effect.

Figure 21.7 Compatibility of liposomes in a System 3TM base.

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The System 3 method is appropriate for virtually any personal care or pharmaceutical application. However, it should be the method of choice with products designed for children, or for anyone with compromised, or sensitive skin. New, unique aesthetic properties can be imparted to the formulated product, thereby creating more elegant systems, and heightening the enjoyment of using the preparation. Since the quality of the product can be maintained so tightly, the consumer will experience the same benefits from purchase to purchase. Brand loyalty will increase with greater compliance to the usage directions.

21.8 Conclusion Surfactant-free formulating offers many advantages versus the conventional method of making emulsifier-based cosmetic, personal care, and drug

products. The compatibility of such Lα-based systems with delivery systems and with the emerging therapeutic agents makes System 3 an ideal formulating vehicle. The novel technical approach provided by System 3 opens the door for a whole new range of possibility for today’s cosmetic chemist. This approach offers a distinction in kind, rather than degree. Its power is so great that it requires cosmetic chemists to enter an unfamiliar realm and think with a completely new mindset. Formulators must be willing to let go of their old “tried and true” ways of thinking about formulating. They must be willing to accept ideas contradictory to well-learned and deeply ingrained principles. If the formulating chemist is truly open to new approaches for creating unique and highly efficacious products, then the use of surfactant-free formulating will provide him (or her) with a powerful new tool that will assist in the development of the next generation of superior personal care and pharmaceutical products.

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21.9 Formulations The Lα dispersions that constitute the System 3 formulating method described in this chpater can be mixed to create topical compositions that possess an almost infinite level of aesthetic diversity. They are generally compatible with the actives and delivery systems being used in today’s cosmetic, OTC,

and pharmaceutical preparations. These properties offer the consumer a wide range of tactitle and visual experiences as well as enhanced performance benefits. Some examples of products that can be made with these dispersions can be found the folowing formulations.

Formulation 21.1: Suncare: SPF 15 Lotion

Phase

Ingredient Moisturizing base

Function

Weight %

Viscosity control

35.25

Deionized water

A

16.75

Advanced moisture complex

Moisturization

1.00

Aesthetic Modifier - 200

Emollient

9.50

Aesthetic Modifier - 300

Emollient

4.50

Aesthetic Modifier - 400

Emollient

11.50

Solarease II

Sunscreen

20.00

Germazide MPB

Preservative

0.50

Liposomes C and E

Antioxidant

1.00 Total

100.00

Mixing Procedure 1. Weigh the moisturizing base into a vessel large enough for the entire batch. 2. With propeller and sweep agitation, add deionized water and mix until a smooth, uniform lotion results. 3. With continued mixing, sequentially add the remaining ingredients ensuring the product is smooth and uniform before adding the next ingredient. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

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Formulation 21.2: Suncare: SPF 50 Plus Cream – Mixed Chemical and Physical Sunscreens

Phase A

B

Ingredient

Function

Weight %

Cationic/acid stable base

Viscosity control

18.30

Germazide MPB

Preservative

TioSperse Ultra TN

Sunscreen

25.00

Solarease OMC/B3

Sunscreen

25.00

SanSurf OC/OS

Sunscreen

25.00

Eusolex HMS

Sunscreen

5.00

Liposomes C and E

Antioxidant

1.00

0.70

Total:

100.00

Mixing Procedure 1. Weigh cationic/acid stable base into a vessel large enough for the entire batch. 2. Add Germazide MPB with propeller and/or sweep agitation. 3. Sequentially add ingredients in Phase B to the main batch. 4. Mix entire batch until it is smooth and uniform. Use homogenizer to increase smoothness and gloss. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

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Formulation 21.3: Suncare: SPF 50 Plus Cream – Chemical Sunscreen

Phase A

B

Ingredient Lotion base

Function

Weight %

Viscosity control

Deionized water

37.00 11.30

Germazide MPB

Preservative

0.70

Aesthetic Modifier - 100

Emollient

5.00

Aesthetic Modifier - 200

Emollient

5.00

Solarease Plus

Sunscreen

30.00

Uvinul N-539-SG (Octocrylene)

Sunscreen

10.00

Liposomes C and E

Antioxidant

1.00 Total

100.00

Mixing Procedure 1. Weigh lotion base into a vessel large enough for the entire batch. 2. Slowly add deionized water to main batch and mix with propeller and/or sweep agitation until system is smooth. 3. Sequentially add ingredients in Phase B and mix until smooth. 4. Mix entire batch until completely uniform. Use a homogenizer to achieve a smooth, glossy appearance. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

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Formulation 21.4: Suncare: Self-Tanning Lotion with Sunscreen Liposomes

Phase

Ingredient

Function

Weight %

Deionized water

72.03

Germazide MPB

Preservative

1.50

Keltrol CG-RD (Xanthan gum)

Thickening agent

0.18

Magnesium aluminum silicate (veegum ultra)

Thickening agent

1.40

Sodium carboxmethylcellulose (CMC 7MF)

Thickening agent

0.56

Unisene 99K (Glycerin, 99%)

Humectant

3.00

Aesthetic Modifier - 300

Emollient

8.00

Sunscreen liposomes

UV absorber

5.00

C

Unitone DH (dihydroxyacetone, 60% aqueous)

Self-tanning agent

8.33

D

Unicept CA (citric acid, 20% aqueous)

pH adjustment

Q.S.

A

B

Total

100.00

Mixing Procedure 1. Weigh deionized water into a vessel large enough for the entire batch. Mix sufficiently to form a vortex. Add Germazide MPB. 2. Sprinkle in the remainder of Phase A and mix until a smooth, uniform fluid results. 3. Sequentially add the ingredients in Phase B and mix until smooth. 4. Add Phase C and mix until smooth. 5. Add a sufficient amount of Phase D to adjust pH to between 5 and 6. 6. Mix entire batch until smooth and uniform. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

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Formulation 21.5: Suncare: After-Sun Lotion

Phase A

Ingredient

Function

Lotion base

Viscosity control

Advanced moisture complex

Humectant

Weight % 35.00 5.00

Deionized water

B

C

20.40

Germaben II

Preservative

0.50

Aesthetic Modifier – 500

Emollient

10.00

Aesthetic Modifier – 600

Emollient

10.00

Aesthetic Modifier – 700

Emollient

10.00

Aesthetic Modifier – 750

Emollient

5.00

SanSurf bisabolol

Anti-irritant

2.00

Activera liposomes

Soothing agent

1.00

Ultrasomes

Repair UV damage

0.50

Photosomes

Repair UV damage

0.50

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Add lotion base to a vessel large enough to contain the entire batch. Mix with propeller and sweep-blade agitation. 2. Slowly add the deionized water and mix batch until it is smooth. 3. Add the advanced moisture complex and mix batch until smooth. 4. Sequentially add the ingredients in Phase B, mixing each until uniform before adding the next ingredient. 5. Add fragrance (if desired) and mix batch until smooth and uniform. Use a homogenizer to assist in this process, if necessary. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

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Formulation 21.6: Moisturizer: Moisturizing Lotion with Moisturizing Liposomes

Phase

Ingredient

Function

Weight %

Deionized water A

B C

55.74

Germazide MPB

Preservative

1.50

Keltrol CG-RD (Xanthan gum)

Thickening agent

0.18

Magnesium aluminum silicate (veegum ultra)

Thickening agent

1.00

Sodium carboxmethylcellulose (CMC 7MF)

Thickening agent

0.25

Unisene 99K (Glycerin, 99%)

Humectant

3.00

Aesthetic Modifier AM – 300

Emollient

33.33

Moisturizing liposomes

Humectant

5.00

Fragrance

q.s. Total

100

Mixing Procedure 1. Weigh deionized water into a vessel large enough for the entire batch. Mix sufficiently to form a vortex. Add Germazide MPB. 2. Sprinkle in the remainder of Phase A and mix until a smooth, uniform fluid results. 3. Sequentially add the ingredients in Phase B and mix until smooth. 4. Add Phase C and mix until smooth. 5. Mix entire batch until smooth and uniform. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards

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Formulation 21.7: Moisturizer: Moisturizing Cream for Oil Skin

Phase

Ingredient Lotion base

A

B

C

Function

Weight %

Viscosity control

38.00

Deionized water

14.90

Aesthetic Modifier - 900

Emollient

8.50

Advanced moisture complex

Humectant

5.00

Germaben II

Preservative

0.50

Unilene BG (butylene glycol)

Moisturizing agent, viscosity control

4.00

SeaMollient

Moisturizing agent, viscosity control

1.50

Aesthetic Modifier - 100

Emollient

8.50

Aesthetic Modifier - 200

Emollient

8.50

Aesthetic Modifier - 300

Emollient

8.50

Humectant liposomes

Moisturizing agent

1.00

Moisturizing liposomes

Moisturizing agent

1.00

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Weigh lotion base in a vessel large enough for the entire batch. 2. Slowly add the deionized water to the batch with propeller and/or sweep agitation. Mix until smooth and uniform. 3. Add the advanced moisture complex and mix the batch until smooth. 4. Add the Aesthetic Modifier - 900 to the batch and mix until it is uniformly dispersed throughout. 5. Sequentially add the ingredients in Phase B to the main batch and mix until smooth and uniform. 6. Add fragrance and mix until uniform. Use a homogenizer, if desired, to make the final product smooth and glossy. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

462

DELIVERY SYSTEM HANDBOOK FOR PERSONAL CARE AND COSMETIC PRODUCTS

Formulation 21.8: Moisturizer: Moisturizing Cream for Normal Skin

Phase

Ingredient Lotion Base

A

B

C

Function

Weight %

Viscosity control

40.00

Deionized water

22.40

Advanced moisture complex

Humectant

5.00

Germaben II

Preservative

0.50

Aesthetic Modifier - 400

Emollient

8.50

Aesthetic Modifier - 500

Emollient

8.50

Aesthetic Modifier - 600

Emollient

8.50

Humectant liposomes

Moisturizing agent

1.00

Moisturizing liposomes

Moisturizing agent

1.00

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Weigh lotion base in a vessel large enough for the entire batch. 2. Slowly add the deionized water to the batch with propeller and/or sweep agitation. Mix until smooth and uniform. 3. Add the advanced moisture complex and mix the batch until smooth. 4. Sequentially add the ingredients in Phase B to the main batch and mix until smooth and uniform. 5. Add fragrance and mix until uniform. Use a homogenizer, if desired, to make the final product smooth and glossy. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

WILMOTT, AUST, BROCKWAY, KULKARNI: THE DELIVERY SYSTEMS’ DELIVERY SYSTEM

463

Formulation 21.9: Moisturizer: Moisturizing Cream for Dry Skin

Phase A

B

C

Ingredient

Function

Weight %

Moisturizing base

Viscosity control

49.40

Advanced moisture complex

Humectant

5.00

Aesthetic Modifier - 900

Emollient

19.00

Germaben II

Preservative

0.50

Unilene BG (butylene glycol)

Moisturizing agent, viscosity control

5.00

SeaMollient

Moisturizing agent, viscosity control

2.00

Aesthetic Modifier - 400

Emollient

8.50

Aesthetic Modifier - 600

Emollient

8.50

Humectant liposomes

Moisturizing agent

1.00

Moisturizing liposomes

Moisturizing agent

1.00

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Weigh moisturizing base into a vessel large enough for the entire batch. 2. Slowly add the advanced moisture complex to the batch with propeller and/or sweep agitation. Mix until smooth and uniform. 3. Add the Aesthetic Modifier - 900 and mix the batch until it is uniformly dispersed throughout. 4. Sequentially add the ingredients in Phase B to the main batch and mix until smooth and uniform. 5. Add fragrance and mix until uniform. Use a homogenizer, if desired, to make the final product smooth and glossy. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

464

DELIVERY SYSTEM HANDBOOK FOR PERSONAL CARE AND COSMETIC PRODUCTS

Formulation 21.10: Moisturizer: Moisturizing Lotion

Phase A

Ingredient

Function

Weight %

Lotion base

Viscosity control

35.00

Advanced moisture complex

Humectant

5.00

Deionized water

B

C

27.40

Germaben II

Preservative

0.50

Aesthetic Modifier - 400

Emollient

10.00

Aesthetic Modifier - 500

Emollient

10.00

Aesthetic Modifier - 600

Emollient

10.00

Humectant liposomes

Moisturizing agent

1.00

Moisturizing liposomes

Moisturizing agent

1.00

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Weigh moisturizing base into a vessel large enough for the entire batch. 2. Slowly add the advanced moisture complex to the batch with propeller and/or sweep agitation. Mix until smooth and uniform. 3. Add the Aesthetic Modifier - 900 and mix the batch until it is uniformly dispersed throughout. 4. Sequentially add the ingredients in Phase B to the main batch and mix until smooth and uniform. 5. Add fragrance and mix until uniform. Use a homogenizer, if desired, to make the final product smooth and glossy. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

WILMOTT, AUST, BROCKWAY, KULKARNI: THE DELIVERY SYSTEMS’ DELIVERY SYSTEM

465

Formulation 21.11: Anti-aging: Anti-aging Cream

Phase

A

B

C

Ingredient

Function

Weight %

Moisturizing base

Viscosity control

45.00

Advanced moisture complex

Humectant

4.00

Deionized water

24.40

Aesthetic Modifier - 900

Emollient

8.00

Germaben II

Preservative

0.50

Unilene BG (butylene glycol)

Moisturizer/viscosity control

5.00

Aesthetic Modifier – 600

Emollient

5.00

Aesthetic Modifier - 700

Emollient

5.00

MatrixyL

Collagen stimulation

0.50

AHA Liposomes

Desquamation

1.00

Actizyme E3M-M

Desquamation

0.50

Rovisome ACE

Antioxidant

0.50

Liposome centella

Collagen stimulation

0.50

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Add moisturizing base to a vessel large enough to contain the entire batch. Mix with propeller and sweep-blade agitation. 2. Slowly add the deionized water and mix until the batch is completely smooth. 3. Add the advanced moisture complex and mix batch until smooth. 4. Add Aesthetic Modifier - 900 and mix until the batch is completely uniform. 5. Sequentially add the remaining ingredients in Phase B, mixing each until uniform before adding the next ingredient. 6. Add fragrance (if desired) and mix batch until smooth and uniform. Use a homogenizer to assist in this process if necessary. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

466

DELIVERY SYSTEM HANDBOOK FOR PERSONAL CARE AND COSMETIC PRODUCTS

Formulation 21.12: Anti-aging: Serum

Phase

Ingredient

Function

Weight %

Deionized water A

B

C

71.05

Universene NA2 (disodium EDTA)

Chelating agent

0.05

Germazide MPB

Preservative

1.00

Keltrol CGRT

Viscosity control

0.60

Unicolic G7 (glycolic acid)

Desquamation

1.50

Unichem LACA (lactic acid, 88%)

Desquamation

5.00

Unichem SOHY25 (sodium hydroxide, 25%)

pH Adjustment

3.10

Aesthetic Modifier - 500

Emollient

10.00

Aesthetic Modifier - 600

Emollient

5.00

MatrixyL

Collagen stimulation

0.10

AHA Liposomes

Desquamation

1.00

Actizyme E3M-M

Desquamation

0.50

Rovisome ACE

Antioxidant

0.50

Liposome centella

Collagen stimulation

0.50

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Add deionized water to a vessel large enough to contain the entire batch. Mix with propeller agitation. 2. Sequentially add EDTA and Germazide MPB mixing each until dissolved before adding the next ingredient. 3. Slowly sprinkle Keltrol CGRT into the batch and mix until smooth and uniform. 4. Sequentially add the remaining ingredients in Phase B mixing until the batch is uniform before the addition of the next ingredient. 5. Add fragrance, if desired, and mix until a smooth, uniform fluid results. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

WILMOTT, AUST, BROCKWAY, KULKARNI: THE DELIVERY SYSTEMS’ DELIVERY SYSTEM

467

Formulation 21.13: Anti-acne: Lotion with Salicylic Acid in Cyclodextrin

Phase

Ingredient

Function

Weight %

Deionized water A

B

68.00

Universene NA2 (disodium EDTA)

Chelating agent

0.05

Germazide MPB

Preservative

1.00

Keltrol CGRT

Viscosity control

0.60

Unicolic G7 (gycolic acid, 99%)

Exfoliant

1.00

Unichem LACA (lactic acid, 88%)

Exfoliant

0.60

Unichem SOHY 25 (sodium hydroxide, 25%)

pH adjustment

1.75

SanSurf Bisabolol

Anti-inflammatory

2.00

Aesthetic Modifier - 200

Emollient

5.00

Salidex

Active (salicylic acid) in cyclodextrin Total

20.00 100.00

Mixing Procedure 1. Weigh the deionized water into a vessel large enough for the entire batch. Begin mixing with propeller agitation. 2. Sequentially add the Disodium EDTA and Germazide MPB. 3. Increase the propeller speed to make a vortex and slowly sprinkle in the Keltrol CGRT and mix until smooth and uniform. 4. Sequentially add the remaining ingredients, mixing each until uniform. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

468

DELIVERY SYSTEM HANDBOOK FOR PERSONAL CARE AND COSMETIC PRODUCTS

Formulation 21.14: Lightening: Serum

Phase

Ingredient

Function

Weight %

Deionized water A

B

C

79.65

Universene NA2 (disodium EDTA)

Chelating agent

0.05

Germazide MPB

Preservative

1.00

Keltrol CGRT

Viscosity control

0.60

Unicolic G7 (glycolic acid)

Desquamation

1.00

Unichem LACA (lactic acid, 88%)

Desquamation

0.60

Unichem SOHY25 (sodium hydroxide, 25%)

pH adjustment

2.00

Unojic A (kojic acid)

Tyrosinase inhibitor

1.00

Vitagen

Pigment inhibitor

0.50

Aesthetic Modifier - 600

Emollient

Rovisome C

Pigment inhibitor

0.50

Melarrest L

Pigment inhibitor

3.00

Actizyme E3M-M

Desquamation

0.50

10.00

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Add deionized water to a vessel large enough to contain the entire batch. Mix with propeller agitation. 2. Sequentially add EDTA and Germazide MPB mixing each until dissolved before adding the next ingredient. 3. Slowly sprinkle Keltrol CGRT into the batch and mix until a uniform, smooth fluid results. 4. Sequentially add the remaining ingredients in Phase B mixing until the batch is uniform before the addition of the next ingredient. 5. Add fragrance, if desired, and mix until a smooth, uniform fluid results. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

WILMOTT, AUST, BROCKWAY, KULKARNI: THE DELIVERY SYSTEMS’ DELIVERY SYSTEM

469

Formulation 21.15: Anti-oxidant: Cream

Phase A

Ingredient

Function

Lotion base

Viscosity control

Advanced moisture complex

Humectant

Weight % 40.00 5.00

Deionized water

B

C

22.80

Germaben II

Preservative

0.50

Aesthetic Modifier - 400

Emollient

10.00

Aesthetic Modifier - 500

Emollient

10.00

Aesthetic Modifier - 600

Emollient

10.00

Scavenol

Antioxidant blend

0.50

Actiquench GTP 20

Antioxidant

0.50

Oxyzomes

Antioxidant

0.50

Coenzyme Q10 Liposomes

Antioxidant

0.10

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Weigh lotion base in a vessel large enough for the entire batch. 2. Slowly add the deionized water to the batch with propeller and/or sweep agitation. Mix until smooth and uniform. 3. Add the advanced moisture complex and mix the batch until smooth. 4. Sequentially add the ingredients in Phase B to the main batch and mix until smooth and uniform. 5. Add fragrance, if desired, and mix until uniform. Use a homogenizer, if desired, to make the final product smooth and glossy. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

470

DELIVERY SYSTEM HANDBOOK FOR PERSONAL CARE AND COSMETIC PRODUCTS

Formulation 21.16: Body Care: Anti-cellulite Lotion

Phase A

Ingredient

Function

Lotion base

Viscosity control

Advanced moisture complex

Humectant

Weight % 35.00 5.00

Deionized water

B

C

41.90

Chlorelline

Skin revitalizing agent

0.50

Germaben II

Preservative

0.50

Aesthetic Modifier – 100

Emollient

5.00

Aesthetic Modifier – 200

Emollient

5.00

Aesthetic Modifier - 300

Emollient

5.00

Firming liposomes

Firming agent

1.00

Vexel

Slimming agent

0.50

Phytotal SL

Slimming agent

0.50

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Add lotion base to a vessel large enough to contain the entire batch. Mix with propeller and sweep-blade agitation. 2. Slowly add the deionized water and mix until the batch is completely smooth. 3. Add the advanced moisture complex and mix batch until smooth. 4. Add Chlorelline and mix until uniform. 5. Sequentially add the remaining ingredients in Phase B, mixing each until uniform before adding the next ingredient. 6. Add fragrance (if desired) and mix batch until smooth and uniform. Use a homogenizer to assist in this process, if necessary. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

WILMOTT, AUST, BROCKWAY, KULKARNI: THE DELIVERY SYSTEMS’ DELIVERY SYSTEM

471

Formulation 21.17: Body Care: Hand and Body Lotion

Phase

A

B

C

Ingredient

Function

Wt. %

Lotion base

Viscosity control

35.00

Advanced moisture complex

Humectant

5.00

Deionized water

28.40

Aesthetic Modifier - 900

Emollient

1.00

Germaben II

Preservative

0.50

Aesthetic Modifier - 500

Emollient

10.00

Aesthetic Modifier - 600

Emollient

10.00

Aesthetic Modifier - 700

Emollient

9.00

Humectant liposomes

Moisturizing agent

0.50

Unisene 99K (glycerin)

Humectant

0.50

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Weigh Lotion base in a vessel large enough for the entire batch. 2. Slowly add the deionized water to the batch with propeller and/or sweep agitation. Mix until smooth and uniform. 3. Add the Advanced moisture complex and mix the batch until smooth. 4. Add the Aesthetic Modifier – 900 and mix until the batch is completely smooth and uniform. 5. Sequentially add the ingredients in Phase B to the main batch mixing each until the batch is smooth and uniform before adding the next ingredient. 6. Add fragrance if desired and mix until uniform. Use a homogenizer if desired to make the final product smooth and glossy. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

472

DELIVERY SYSTEM HANDBOOK FOR PERSONAL CARE AND COSMETIC PRODUCTS

Formulation 21.18: Hair Care: Styling Cream

Phase A

Ingredient

Function

Lotion base

Viscosity control

Advanced moisture complex

Humectant

Weight % 50.00 1.50

Deionized water

B

C

31.40

Germaben II

Preservative

0.50

Aesthetic Modifier - 300

Emollient

PVP/VA W735

Hair fixative

6.00

Humectant liposomes

Moisturizing agent

0.50

Fragrance

0.10 Total

100.00

Mixing Procedure 1. Weigh lotion base in a vessel large enough for the entire batch. 2. Slowly add the deionized water to the batch with propeller and/or sweep agitation. Mix until completely smooth and uniform. 3. Add the advanced moisture complex and mix the batch until smooth. 4. Sequentially add the ingredients in Phase B to the main batch mixing each until the batch is smooth and uniform before adding the next ingredient. 5. Add fragrance, if desired, and mix until uniform. Use a homogenizer, if desired, to make the final product smooth and glossy. This formula is offered for informational purposes to represent a particular product concept. There is no expressed or implied warrantee regarding its use in commerce. The authors are not responsible and should be held harmless for any regulatory, legal, performance or safety liabilities that that may result from its use. Each individual or company is encouraged to conduct the appropriate due diligence to insure the formula meets internal corporate standards.

References

6. Rieger, M., Cosmetics and Toiletries, 110(4) (1995)

1. Jass, H. E., The Chemistry and Manufacture of Cosmetics, 2nd Ed., (M. G. DeNavare, ed.), p. 237, Continental Press, Orlando (1975)

7. Kawasaki, Y., Quan, D., Sakamoto, K., and Maibach, H. I., 18th International IFSCC Congress, pp. 37–50 (1994)

2. Henry, C. M., Chemical and Engineering News, 80(34) (2002)

8. Casterton, P. L., Potts, L. F., and Klein, B. D., Toxicology In Vitro, 8(4) (1994)

3. Effendy, I., and Maibach, H. I., Contact Dermatitis, 33(4) (1995)

9. Bielfeldt, S., Parfuem Kosmet, 71(5) (1990)

4. Barany, E., Lindberg, M., and Loden, M., Contact Dermatitis, 40(2) (1999)

10. Walters, K. A., Methods for Predicting the Effect of Surfactants on Skin, Seminar at In Cosmetics, Birmingham, UK (1990)

5. Rhein, L. D., J. Society of Cosmetic Chemists, 48(5) (1997)

11. Zeidler, U., J. Society of Cosmetic Chemists, Japan, 20(1) (1986)