EMULFEEL SGP CHI. DESCRIPTION Structuring of vegetal oil in the presence of Monoglycerydes, Esters and Polymers (patent application filled under PCT).

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1 EMULFEEL SGP CHI DESCRIPTION Structuring of vegetal oil in the presence of Monoglycerydes, Esters and Polymers (patent application filled under PCT). COMPOSITION INCI NAME CAS N EINECS (I)/ELINCS (L) Helianthus Annuus (Sunflower) Seed Oil (I) Sodium Polyacrylate Polymer Xylitol (I) Caprylic Acid (I) Glyceryl Stearate (I) INTRODUCTION Organogel The organogel technology is a novel method of oily structuring which has been object of considerable interest because of the potential to structure vegetal oils or other organic compounds using small concentrations (minimum 0.5%) of structuring agents, also from vegetal sources. This technology is based on principles that promote sustainability since the technology is very economically efficient, produces no waste and uses natural and renewable products of rapid environmental degradation. Organogel can be defined as a thermo-reversible viscoelastic material formed from the immobilization of organic fluids by a three-dimensional gel network. This network is formed by physical or chemical interaction of structuring agent molecules which prevents the nonpolar phase to flow. In other words, organogels are materials with characteristics and rheological properties of a solid, but with greater part of its composition (~ 98%) being an organic liquid (Figure 1) 1, 2. EMULFEEL SGP CHI Pág. 1/11

2 Figure 1. Organogel technology concept where structuring agents at low concentrations are combined with oils producing a gel network capable of sustaining a high concentration of the oily phase. The inverted beaker shows the gelation of 97% oil phase by 3% of structuring agent. The organic fluid can be any liquid that may suffer any form of structuring by the organogelator. The polarity of the organic compounds can vary depending on its structure and can affect negatively or positively its structuring process. Examples of organic fluids of interest in cosmetics are vegetal oils, mineral oils and silicones. In recent years, vegetal oils have been a trend in the cosmetics field. These are ecological raw materials derived from natural and renewable sources, which promise to bring active principles in order to treat and nourish skin and hair. Vegetal oils can be derived from a variety of fruits and seeds, such as soybeans, corn, canola, rice, avocado, palm, olive, coconut, almond, grape seed, cotton, sunflower etc. 2. Receiving a differentiated refinement these oils may be natural sources and rich in antioxidants, vitamins and phospholipids. However, the selection of vegetal oil should be done carefully, with special attention to the odor and stability of the oil. 3 The structuring agent, also referred as organogelator, is compounds that undergo a self-assembled molecular orientation when solubilized in a fluid, resulting in a gel network capable of supporting a large volume of liquid. Covalent interactions, van der Waals, electrostatic and hydrogen bonds are examples of intermolecular forces responsible for the formation of the gel network 1,2. A variety of publications and studies describe different types of structuring agents for pharmaceutical, cosmetics, petrochemicals and food applications. Among them are EMULFEEL SGP CHI Pág. 2/11

3 synthetic and mineral compounds such as polyethylene or polyalkylene glycol, polycarbonate, polyester, paraffin, synthetic tripeptide, synthetic derivatives of L-lysine and derivatives of cyclohexane (4-tert-butyl-1-aryl cyclohexanes) as well as gelling agents of natural sources such as fatty alcohols and acids of vegetal origin (12-hydroxystearic acid), esters wax (rice bran wax, carnauba and candelilla), monoacylglycerols (glyceryl monopalmitate and glyceryl monostearate), phospholipids (lecithin) and phytosterols (γoryzanol) and more recently ceramides 3,4,5,6,7,8. Monoglycerides are well known emulsifiers and widely used in food and cosmetics products due to its ability to gel and structure lipid and aqueous systems. With the ability to also modify the physical properties of oils due to their amphiphilic nature, a great interest in monoglyceride have led to many studies on the development of organogels with the same characteristics of the hydrogels made with monoglycerides 9,10,11. The potential of organogel technology in the cosmetic area goes from a simple vegetal oil structuring as a substitute for silicone oil gels, to the usage of this technology as a vehicle for the penetration of actives into the skin. Despite the potential, this is a novel technology and its application is still limited. Application examples include the structuring of flammable solvents, medicated cosmetics, cooking oil disposal, solvents for cleaning oil paints, etc 6. Emulsions Emulsion is a colloidal system consisting of a mixture of two immiscible fluids. Its stability is conferred by different variables such as temperature, composition and droplet size distribution. In cosmetics, oil and water are the major components of the emulsions, and may contain other dispersed hydrophobic and hydrophilic components respectively. By being immiscible, the combination of the two liquids requires tensoactives or polymers to enable the formation of the emulsion. Tensoactives adhere to the interface created and reduce the surface tension which enables the formation of the emulsion. Polymers are able to gel the continuous aqueous phase by forming a three-dimensional gel network that increase viscosity, reducing the mobility of the oil droplets, and facilitates dispersion of the oily phase. Conventional emulsions can be classified as oil/water (O/W), when oil is the dispersed phase and water is the continuous phase, and water/oil (W/O) when water is the dispersed phase and oil is the continuous phase. 12,13 There are also more unconventional types of emulsions called multiple emulsions and lamellar emulsions. Multiples emulsions are known as water/oil/water (W/O/W) and oil/water/oil (O/W/O) emulsions where the dispersed phase is already an emulsion. The lamellar emulsions are formed with an excess of emulsifier which is organized in bilayers separated by aqueous layers. Oil/water emulsions are the most common in the cosmetics EMULFEEL SGP CHI Pág. 3/11

4 field. These are manufactured in the form of creams and lotions that differ in composition and viscosity or fluidity 14,15. Oil/water emulsions, as well as the others, are thermodynamically unstable, in other words, they separate over time. The longer these emulsions lead to destabilization, the safer the formulation is considered. Stabilizers and emulsifiers are responsible for stability throughout the process of emulsion formation. In the beginning of the process, the agitation step breaks of the oily phase leading to the formation of the oil-water interface. The interface is primarily stabilized against coalescence by the emulsifier. Stabilizers take longer to adhere to the interface, but have a greater ability to stabilize the system and ensure longer shelf-life. Cold Process Emulsion The conventional way of preparing cosmetic emulsions is through a hot process. In order to stabilize these emulsions, polar and nonpolar phases are heated and combined with the use of high agitation and in the presence of surfactants, a process that requires time, energy, and specific equipments. For this and other reasons, the cold process emulsion has been of great interest by the industry in trying to create emulsions of equal quality, but with reduced process time and cost compared to hot process emulsions. The use of surfactants is the most common practice for the stabilization of cold process emulsions. However, a few liquid emulsifiers, which are able to be processed cold, can ensure a good performance on stability and sensory effect of emulsions. The use of rheological modifiers to structure the aqueous phase of the emulsion is another option for the stabilization of such emulsions. Its use facilitates dispersion by gelifying the continuous phase of the emulsion and increasing the stability and consequently the shelf-life of the product. As known, emulsion is the main galenical form in the cosmetics industry. The choice of emulsifier is thus essential, since it has many implications in the manufacturing process as well as in the texture of the final product. EMULFEEL SGP CHI was created with the purpose of facilitating the preparation of oil/water emulsions. Developed with the organogel technology, the product has in its composition compounds capable of gelifying the water and oily phase of the emulsion. This dual structuring, associated with an increase of the viscosity of aqueous and oily phase, promises to increase system stability against coalescence of globules without the use of surfactants in the formulation or high agitation in the process. The main advantage of the product is its easy application that is done by incorporation of the oily phase in the aqueous phase as shown in Figure 2. The oil and water phases may include the addition of other components in the formulation. With stirring an emulsion is obtained with excellent dispersion of globules (Figure 3). EMULFEEL SGP CHI Pág. 4/11

5 Figure 2. Schematic representation of the formation and stabilization of an O/W emulsion formed from the dispersion of EMULFEEL SGP CHI in water. Figure 3. Optical micrograph of an O/W emulsion prepared using EMULFEEL SGP CHI. The performance of the product is in the process conditions and on the structure of emulsions formed, besides enabling the anticipation of sensorial attributes. Thus, the EMULFEEL SGP CHI FQ MKT_003 (03/13) SA 10076/14 Pág. 5/11 LT 780 Rev I

6 rheological and thermal properties are essential for its characterization and exert great effect on the quality of the final product. Figure 4 and 5 illustrate the behavior of emulsions, formed from the dispersion of 1, 3 and 5% of EMULFEEL SGP CHI in water, when under shear. Figure 4. Flow curve of emulsions formed from the dispersion of 1, 3 and 5% of EMULFEEL SGP CHI in water. The results shown correspond to an initial increase in shear rate followed by a decrease and a second increase of shear rate. As noted, the formed emulsions require a low shear stress to initiate flow; on the order of 0.2 Pa at a concentration of 1% of EMULFEEL SGP CHI and 12 Pa at a concentration of 5% of EMULFEEL SGP CHI. A low yield stress facilitates dispersion and flowing, as well as other steps in the manufacturing of emulsions. EMULFEEL SGP CHI Pág. 6/11

7 Figure 5. Evolution of the viscosity of emulsions formed from the dispersion of 1, 3 and 5% of EMULFEEL SGP CHI in water. The results correspond to a first increase in shear rate followed by a decrease and a second increase of the shear rate. As noted, the emulsions exhibit shear thinning behaviour since its viscosity decreases with the increasing of shear rate. This phenomenon is expected for this product and it is independent on the EMULFEEL SGP CHI concentration used (within the suggested use concentration). The emulsion formed also has a non-thixotropic character as the viscosity decreases with increasing shear but recovers immediately after removal of shear, going back to its initial viscosity value. These results demonstrate the ability of the product EMULFEEL SGP CHI to generate emulsions that are simple to be prepared, have good appearance and viscosity at rest and are easy to be applied on the skin (good spreadability). Viscoelasticity The rheological properties of the emulsions were also evaluated by an oscillatory test. As seen in Figure 6, the values of elastic modulus, for an emulsion formed from the dispersion of 3% of EMULFEEL SGP CHI in water, are always higher than the values of viscous modulus within the frequency range assessed. The high values of the viscoelastic gel clearly show the character of the emulsions evaluated as well as their resistant structure. These results are also correlated to the light texture of emulsions, forming products with excellent sensory characteristics, and physical stability. EMULFEEL SGP CHI Pág. 7/11

8 Figure 6. Oscillatory study of an emulsion formed from a dispersion of 3% EMULFEEL SGP CHI in water. G = Elastic Modulus; G = Viscous Modulus. Temperature Resistance The rheological behavior of an emulsion, formed from a dispersion of 3% of EMULFEEL SGP CHI in water, was investigated using an oscillatory study where the temperature varied from 5 to 80 C. As can be seen, there was no significant variation of the structure of emulsions within the measured temperature range indicating good stability of emulsions if subjected to atypical temperatures, both at process and storage conditions. EMULFEEL SGP CHI Pág. 8/11

9 Figure 7. The evolution of G and G moduli when the temperature varies from 5 to 80 o C in a oscillatory study WHY USE IT? EMULFEEL SGP CHI can be used in the preparation of creams, gel-creams and lotions for cosmetic products which requires the formation of oil/water emulsions. Its main attributes are: - It promotes, by a cold process, stable emulsions with no need for high mechanical agitation; - It promotes the structuring of the oily and aqueous phase of emulsions, which have an influence on the sensory and stability of oil/water emulsions; - Promotes emulsions with superior touch, even when used with emollients which are known to have an oily character, such as mineral oil; - Acts as a viscosity raiser; - Compatible with a variety of formulations containing mixtures of different hydrophilic and lipophilic components; - Excellent ability in the formation and stabilization of emulsions without the addition of surfactants; - Greater part of its composition is formed by vegetal compounds; - Moisturizing effect, for carrying in its medium the dispersion of natural waxes, and other lipid crystals, that forms a lipophilic film, enhancing water retention; EMULFEEL SGP CHI Pág. 9/11

10 - Due to its complete formulation, it can also be used in the preparation of hot process emulsion; - Clinical, dermatological and ophthalmological safety proven. APPLICATION AND TECHNICAL ASPECTS EMULFEEL SGP CHI can be used in the preparation and stabilization of oil/water emulsions by a cold process. Technical aspects: Incorporation done at room temperature, where EMULFEEL SGP CHI is preferably dispersed in the oily phase followed by their dispersion in the aqueous phase; Can be incorporated by a hot process; EMULFEEL SGP CHI is available in the solid form, due to its crystalline structure; EMULFEEL SGP CHI should not be overly manipulated before use, as this may compromise its crystal structure; EMULFEEL SGP CHI showed compatibility with the addition of different emollients and actives. However, due to its anionic characteristic, it is not stable in the presence of cationic and electrolytic medium. Emulsion formed is stable at ph between 5.0 to 10.0 SUGGESTED USE LEVEL From 2.0 to 5.0% (w/w) depending on the application (structuring agent or viscosity adjustment), as well as the composition and viscosity required by the cosmetic formulation. BIBLIOGRAPHICAL REFERENCES 1. Abdallah AJ, Weiss RG Organogels and low molecular mass organic gelators. Advanced Materials. 12: Weiss RG, Terech P Introduction. In: Weiss RG, Terech P, editors. Molecular Gels Materials with Self- Assembled Fibrillar Networks. Dordrecht (NL): Springer. p Gunstone FD, Harwood JL, Dijkstra AJ The Lipid Handbook. 3 rd edition. New York (NY): Taylor & Francis Group. p Terech P, Weiss RG Low Molecular Mass Gelators of Organic Liquids and the Properties of Their Gels. Chemical Reviews. 97(8): Kumar R, Katare OP Lecithin Organogels as a Potential Phospholipid-Structured System for Topical Drug Delivered: A Review. AAPS PharmSciTech. 6 (2): EMULFEEL SGP CHI Pág. 10/11

11 6. Pernetti M, van Malssen KF, Floter E, Bot A Structuring edible oils by alternatives to crystalline fat. Current Opinion in Colloid and Interface Science. 84: Hughes NE, Marangoni AG, Wright AJ, Rogers MA, Rush JWE Potencial food applications of edible oil organogels. Trends in Food Science & Technology. 20: Sahoo S. Kumar N, Bhattacharya C, Sagiri SS, Jain K, Pal K, Ray SS, Nayak B Organogels: Properties and Applications in drug delivery Designed Monomers and Polymers 14 : Rogers MA, Wright AJ, Marangoni AG Ceramide Oleogels. In: In: Marangoni AG, Garti N, editors. Edible Oleogels: Structure and Health Implications. p O'Brien, R. D Fats and oils: formulating and processing for applications. 2nd ed. Boca Raton (FL): CRC press. p Ojijo NKO, Neeman I, Eger S, Shimoni, E Effects of monoglyceride content, cooling rate and shear on the rheological properties of olive oil/monoglyceride gel networks. Journal of Food Science and Agriculture. 84: McClements DJ Food emulsions: principles, practices and techniques. 2 nd ed. Boca Raton (FL): CRC Press. p Mitsu T New Cosmetic Science. Amsterdam (NH): Elsevier. p Jiao J, Burgess DJ Multiple Emulsion Stability: Pressure Balance and Interfacial Film Strength. In: Aserin A, editor. Multiple Emulsions Technology and Applications. Hoboken (NJ): John Wiley & Sons, Inc. p Ryklin I, Byers B Shear-Thinning Lamellar Gel Network Emulsions as Delivery Systems. In: Rosen MR, editor. Delivery System Handbook for Personal Care and Cosmetic Products: Technology, Applications and Formulations. Norwich (NY): William Andrew. p Document Written by: Revised by: Approved by: Controlled by: R&D Dept. Marketing Dept. R&D Director Quality Assurance Dept. Information contained in this literature is provided on good faith. We recommend that our products are tested in order to check for the convenience of their usage before adopting them on an industrial level. Such information should not be understood as a concession or allowance for using methods or compositions covered by any patent. Reproduction and distribution of this material without prior authorization from CHEMYUNION QUÍMICA LTDA are forbidden EMULFEEL SGP CHI Pág. 11/11