NEW PEG-FREE MULTIFUNCTIONAL CO-SURFACTANT BASED ON NATURAL ORIGIN

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1 NEW PEG-FREE MULTIFUNCTIONAL CO-SURFACTANT BASED ON NATURAL ORIGIN Marchesi Flavio, CISME Italy srl - Via Giuseppe Marcora Milano (Italia) Abstract Modern concepts of wellness for personal care products require ingredients with improved performance and increased attention to both skin equilibrium and to the environment. These needs make producers of personal care and household detergents look for raw materials from renewable natural origin that can be friendly to the environment without compromising washing efficiency and without adverse side effects or allergic potential. Formulators also have to consider traditional requirements such as formula cost, viscosity, stability, foam density, etc.. For each of the single above mentioned characteristics already exists on the market several ingredients, which work positively on some aspects but often negatively on others, obliging the formulator to introduce additional ingredients to establish a balanced compromise. Personal care and household detergents such as hand soaps, shampoos, shower gels, foam baths etc..are mainly based on surfactants named primary surfactants as well as additional surfactants named secondary surfactants or co-surfactants. The functionality purpose of secondary surfactants is to improve some characteristics in the basic formulae, such as detergency effectiveness, foam, viscosity, reduction in skin irritation, skin feel during and after wash, etc.. In rinse-off products consumers require characteristics such as; excellent washing efficiency, good foaming proprieties (also in hard water), good viscosity / rheological behaviour (often considered by consumers an index of concentration), skin compatibility during and after wash, as well as acceptable cost. Putting together all such requirements and properties is the final goal of each formulator. For the purpose of satisfying the various characteristics needed in detergents and personal care products, several secondary surfactants have been introduced in the last ten years. Generally speaking each secondary surfactant acts in the formulation on some specific characteristics, but at the same time also has negative effects on other desired characteristics; for example, Sodium Lauroyl Glutamate has well known benefits to skin but dramatically reduces viscosity in formulation, CocoDEA increases the viscosity of the formulation, but at the same time decreases the washing efficiency, and has a nitrosamine problem. Some are solid such as CocoMEA, and require melting with negative effects on production cost. Alternative substances are also available to increase the viscosity, such as synthetic polymers (acrilates, carbomers ), or natural polymers such as xantham gum for cosmetics applications, both types however show negative skin-feel and do not have any positive influence on washing efficiency. The aim of this article is to draw the attention of the formulator to a new PEG Free multifunctional secondary surfactant for personal care and household products, easy to use and formulate, that offers several application advantages and can resolve different problems simultaneously. Its use in the formulation grants several application benefits, allowing the use of one single product instead of dissimilar ingredients which would also result in an increase in formula cost. Multifunctional PEG-Free Co-surfactant The functional characteristics of this secondary co-surfactant, composed of a synergic base of biodegradable surfactants totally of natural origin, can be summarized in its ability to increase the washing efficiency, increase the foam stability and density, increase the viscosity when electrolytes are added, reduce skin irritation caused by primary surfactants and above all have a protecting, soothing and restoring ability that grants immediate feel of hydration, smoothness and softness. DITEROL AL4PF Belongs to a new generation of multifunctional co-surfactants ethylene oxide free, based on natural active ingredients which thanks to the presence of long chain fatty acids, deriving from Olive oil, such as Oleic, Linoleic, Linolenic acids and Wheat Protein (oligosaccharides) as well as Myristyl Lactate constitute a unique hydrating complex offering a combination of moisture balancing and film forming properties working synergistically to give better bounce to the hair, and smoother, softer feel to the skin. INCI Name Potassium Olivoyl Hydrolyzed Wheat Protein and and Myristyl Lactate CAS number Apparence Pourable paste Colour Yellowish Odour Slightly olive Active matter 4 +/- 2% ph (1%sol) 6,5 7,5

2 In this article we will evaluate the performance of Diterol AL4PF at a dosage of 2% in weight. 1. With Sodium Lauryl Ether Slufate only 2. With SLES in presence of Cocamidopropyl Betaine 3. With SLES in presence of Cocamidopropyl Betaine and Sodium Lauroyl Glutamate. 4. With SLES in presence of Cocamidopropylamin Oxide and Sodium Laureth Sulfosuccinate 5. In vitro reduction evaluation of skin irritation with respect to SLES With SLES only VISCOSITY 2% addition of Diterol AL4 PF in weight, to SLES at 1% active matter highly increases viscosity, in presence of electrolytes Table Viscositi mpas at 25 C with 2% w/w DITEROL AL4PF whitout 2% w/w DITEROL AL4PF, 1, 2, 3, 4, Table 1 With SLES only FOAMING ABILITY 2% addition of DiterolAL4 PF to SLES solution at 1 % a.m markedly increased the foams tability and produced smaller bubbles compact and dense. Table with 2% w/w DITEROL AL4PF whitout 2% w/w DITEROL AL4PF Table 2. In a graduated cylinder using 2ml of water +.1g of blend after 1 strokes observing height and aspect of foam immediately and after 3 and 12 ( hard water 1 French degree)

3 With SLES in presence of Cocamidopropyl Betaine VISCOSITY 2% addition of Diterol AL4PF in weight, to SLES at 14% active matter and Cocamidopropyl Betaine at 1.5% active matter highly increases viscosity in presence of minimum quantities of salt Table Viscosity mpas at 25 C with 2% w/w DITEROL AL4PF whitout 2% w/w DITEROL AL4PF,5 1 1,5 2 2,5 Table 3. With SLES in presence of Cocamidopropyl Betaine FOAMING ABILITY 2% addition of DiterolAL4 PF markedly increased the foam stability and produced smaller bubbles compact and dense. Table with 2% w/w DITEROL AL4PF whitout 2% w/w DITEROL AL4PF Table 4. In a graduated cylinder using 2ml of water +.1g of blend after 1 strokes observing height and aspect of foam immediately and after 3 and 12 ( hard water 1 French degree)

4 With SLES in presence of CAPB and Sodium Lauroyl Glutamate VISCOSITY 8.4% a.m. SLES.9% a.m. Cocamidopropyl Betaine.8% a.m. Sodium Lauroyl Glutamate.8% a.m. Diterol AL4 PF (2% in weight) Water + NaCl to 1% 2% addition of Diterol AL4PF in weight, markedly increased viscosity even in presence of Sodium Lauroyl Glutamate known to have dramatic effects on viscosity Table 5 Viscosity mpas at 25 C ,,5 1, 1,5 2, 2,5 3, 3,5 with 2% w/w DITEROL AL4PF whitout 2% w/w DITEROL AL4PF Table 5. With SLES in presence of CAPB and Sodium Lauroyl Glutamate FOAMING ABILITY 2% addition of DiterolAL4 PF markedly increased the foam stability and produced smaller bubbles compact and dense. Table with 2% w/w DITEROL AL4PF whitout 2% w/w DITEROL AL4PF Table 6. In a graduated cylinder using 2ml of water +.1g of blend after 1 strokes observing height and aspect of foam immediately and after 3 and 12 ( hard water 1 French degree)

5 With SLES and Cocamidopropylamine Oxide and Sodium Laureth Sulfosuccinate - viscosity 12,25% a.m. SLES 1,% a.m. Cocamidopropylamin Oxide,6% a.m. Sodium laureth sulfosuccinate.8% a.m. Diterol AL4PF (2%in weight) Water and NaCl to 1% 2% addition of Diterol AL4PF in weight, markedly increased viscosity even at low salt Table Viscosity mpas at 25 C with 2% w/w DITEROL AL4PF whitout 2% w/w DITEROL AL4PF,,5 1, 1,5 2, 2,5 Tab 7. With SLES and Cocamidopropylamine Oxide and Sodium Laureth Sulfosuccinate - FOAM 2% addition of DiterolAL4 PF markedly increased the foam stability and produced smaller bubbles compact and dense. Table with 2% w/w DITEROL AL4PF whitout 2% w/w DITEROL AL4PF Tab 8. In a graduated cylinder using 2ml of water +.1g of blend after 1 strokes observing height and aspect of foam immediately and after 3 and 12 ( hard water 1 French degree)

6 IN VITRO EVALUATION OF SKIN IRRITATION POTENTIAL In vitro methods are an interesting alternative system to traditional vivo test to evaluate biological properties of topical products and cosmetics (according with European cosmetics rules that ask manufacturers to assess the product safety and effectiveness, without employing animals, BCD n 76/768/ECC of the 27/7/76, EC L.262 of the 27/9/1976; VI amendment Council Directive 76/768 EEC of the 14/6/1993 ECKL 151 of the 23/6/1993). Cytotoxicity assay can be carried out in order to evaluate in vitro the potential skin irritation of cosmetic ingredients or finished products on keratinocyte cultures. The in vitro test on skin-derived cells is a simplified but yet very informative model of the reaction that may occur in vivo. Products are directly applied locally on human skin or hair, often in contact with mucous membranes. The cytoxicity assay performed in this study was designed to evaluate the toxic dermal irritation potential of tested products using relevant human cell grow in vitro. Cytotoxicity test performed on human keratocites of fibroblasts in mono-layers have been extensively used in the evaluation of eye and skin irritation potential of cosmetics and ingredients. The objectives of this assay is to assess quantitatively the effects of the products on the cell survival trough the MTT assay; this is a very simple colorimetric assay that allows to determinate the percentage of living cell within cell cultures. This method has been developed originally bu Mossman,. The key reagent is 3(4,5- dimethylthiazol-2-yl)-2,5-diphenil tetrazolium bromide or MTT. Mithocondrial dehydrogenases of viable cell cleave the tetrazolium ring, leading to the formation of purple crystals, salt of formazan. An increase or decrease in cell number results in a concomitant change in the amount of formazan formed, indicating the degree of cytotoxicity caused by the tested material.. IC5 ( Inhibiting concentration 5%) : concentration of test compound which causes a 5% decrease of cells survival as compared to untreated cells. The IC5 value ( Inhibition Concentration 5) is the concentration of test compound which induce a 5% decrease of cells growth / survival. It makes it possible to evaluate the potential irritating effect of the compound. With MTT we tested Lauryl Ether Sulphate( SLES) 13% a.m. on its own as well as in combination with 2% Diterol AL4PF to evaluate the eventual decrease in terms of potential irritation PRODUCT IC 5 mg/ml EVALUATION SLES 13% a.m..8 Slightly irritant SLES 13% a.m. + 2% Diterol AL4PF w/w 5.1 Very good biocompatibility IC 5 < 1 mg/ml = irritating product IC 5 > 3 mg/ml = very good biocompatibility EVALUATION A blend of 13% a.m. SLES and 2% w/w Diterol AL4PF resulted 6 times less cytotoxic than SLES on its own confirming Diterol AL4PF ability to reduce potential irritation of primary surfactants. CONCLUSION The significant characteristics of this multifunctional co-surfactant is given by the presence of long chain fatty acids, deriving from Olive oil, Wheat protein and Myristyl Lactate. Their presence explains the results of the tests carried out on the surfactants concerning their highly smoothing performance. A number of scientific tests show, in fact, that the molecules with short chain fatty acids, have a greater irritant power than the long chain fatty acids whereby the irritant power of a surfactant is influenced by the number of carbon atoms the fatty acid present in the molecule is made of. These fatty acids of olive oil bond to wheat proteins have more similarities to both cutaneous secretion (sebum) and the cutaneous structures themselves (cheratine) making the Olivoil products very tolerable at cutaneous level and thus giving the finished products containing them a very nice psychoreologic effect. The Olivoil products carry out an effective functional action, very soft and moisturizing, in the respect of a correct cutaneous physiology. They leave on the skin a good feel of hydration, smoothness, softness and cleansing. After using a detergent containing Diterol AL4PF, one has a feel of cleanliness, satisfaction and well-being.

7 PERFORMANCE SUMMARY Combines the performance of low irritating surfactants free of ethylene oxide with emollient and restructuring skin agents due to the presence of derivatives of Olive oil, Wheat Protein and Myristyl Lactate which benefits are well known and demonstrated in literature Reduces substantially the irritancy of commonly used surfactants. Excellent viscosity booster free of nitrosamine. Produces stable and compact foam granting a creamy sensation on application. In dosage above 3% it exhibits deodorant proprieties thanks to the anti bacteria action deriving from the hydrolysis of ester (sniff test) The deodorant effect is linked to the presence of lactate in formulation whose deodorant effect is well known and demonstrated in literature Its presence in a liquid detergent helps the skin to restore its healthy aspect by avoiding the denaturation of proteins and the disorganisation of the horny layer. Easy to use and compatible with all primary anionic and amphoteric surfactants Bibliography 1. Bothan P.A., Earl L.K, Fentem J.H. Rouuet R. Van De Sandt J.J.M ( 1998) Alternative methodsfor skin irritation testing : the current status ATLA Kupper, T.S. (199) Immune and inflammatory processes in the cutaneous tissue: mechanisand speculatuion Jour..Clin.Invest 3. Norma UNI EN ISO Valutazione biologica dei dispositivi medici- Prove per la citotossicità in vitro Settembre 2 4. S.Amari, A.Amari, C.Schubert, Olive oils surfactants, B&T Milano 5. Genova C., Zatta A.,Deiana L., Montesion F. Mono-branched alkyl lactate as a rheological improver for body and personal care formulations Condea Italy 6. K.F.De Polo, Textbook of Cosmetology, Verlag Gemany 7. D Angelo M, Proserpio G, Rastrelli GB: An Olive Oil- and Wheat-derived Lipoprotein Emulsifier - C&T,116 (21) 8, Kiritsakis AK: Virgin olive oil composition and its effect on human health - Inform, (13) 3 (22), Head Office and Production: Via G. Pastore, Botticino Sera (BS) ITALY Tel: Fax: kalichem@kalichem.it www