Date du stage

du 01.07.2010

au 31.12.2010

Stage année de césure :

1ersemestre

Année 2010/2011..

De Marco Marine

Spécialité : CGP

Confidentialité du rapport : OUI

Titre du rapport en français : Formulation d´emulsions,

gels cosmétiques au sein au sein du laboratoire de

développement Asie et Amérique Latine.

Titre du rapport en anglais : Formulation of emulsions,

gels in product developement for Asia and Latam

America

Beiersdorf AG

Hamburg Deutschland

Mr Bleckmann AndreasFunction : Laboratory Manager

SUMMARY

THANKS

1)Presentation of the company

1.1)Company introduction

Beiersdorf is a global player in Skin Care founded in 1882. NIVEA is the biggest skin & beauty care brand worldwide. Eucerin is a leading dermo-cosmetic brand, sold primarily in pharmacies La Prairie is a brand icon in the selective anti-aging skin care market. NIVEA is available in more than 200 countries of the world.. More than 20,000 employees are working with passion all over the world.

1.2)Background Information

The continuous development since the Company was founded in 1882 has made Beiersdorf a global leader. Beiersdorf started internationalizing of the business early and signed the first cooperation agreement with an American trading company back in 1893. The innovative skin care brands are appreciated all over the world. Systematic advancement of all our brands ensures they are always up to date – and that they are reliable companions for your daily skin care.With targeted acquisitions like La Prairie (1991), Florena (2002) or C-BONS Hair Care (2007), Beiersdorf complete the broad range of products.

125

125

125

125

125

125 years of Innovative Skin Care

1.3) Research Center

Research center is one of the largest and most advanced research centers in Europe. The Research and Development has worked tirelessly ever since the Company was founded, repeatedly setting new standards. In 1911, NIVEA was the first long-lasting water-and-oil-based cream in the world: Eucerit Most of the research and development work takes place in the Skin Research Center in Hamburg (Germany).There are two additional regional development centers in Zurich (Switzerland) and Wuhan (China). They work closely with the researchers in Hamburg and regularly exchange their research findings, thus boosting our innovative strength.In Hamburg (Germany), Beiersdorf has established a special Asia Laboratory to develop tailored products for the Asian markets. The LATAM Laboratory develops products especially for Brazil and other countries in Latin and South America.The Research team for the Consumer Business segment is

around 550 scientists worldwide.R&D expenses in 2009: €149 million .In 2009, Beiersdorf has done 133 patents for innovations.

2) My internship in the regions

2.1) MissionI have worked on different projects for the brand Nivea which consist to develop, optimize

new formulas, evaluate the sensory properties and follow the different steps of the project.My main projects were focus on the development of a formula with a high SPF up to 50 and to

work on a patent to demonstrate the use of Acrylate Crosspolymer.(Acrylamide/Ammonium Acrylate Copolymer + Polyisobutene + Aqua + Polysorbate 20). The other project concerns the development of Whitening Day Care for Latam America, the perfume test and packaging compatibility. My last projects was to develop a spot corrector for visage for Asia.

2.2) ObjectiveMy objective was to do with success these three main projects and to build up knowledge

concerning the raw materials( UV filters especially), the attendance at scale up process ,the different kind of formulation and how a product is created. The goal was also to learn concerning the regions( Latam America and Asia).

2.3) CourseI have been in charge of different projects and I will develop three mains projects. In fact, my

times was shared for working on my own projects and to help my colleagues for some supports. It was very interesting because I have had the possibility to see different kinds of methods and products such as O/W emulsion, gels, dispersions My intership took place product development for Latam America and Asia. I have worked in both labs where 10 people are working.

Annex organigramme

2.4) Introduction to the regions: Latam America and Asia:

Those both are working together for mostly all the projects. Beiersdorf have created those two labs to satisfy the needs of men and women in Latam America and Asia which are not the same as in Europe for example.Asia and Latam America like light products, non sticky formulas, dry and shiny formulas. They have to develop new products such as whitening products or Acclarado.The difficulty for these countries is focus on the costs of the product. That´s why the research needs to be always closer to the market. Those laboratories are always working in interaction with the local employees and marketing. They work on developing innovated formulas which are going to be on the market in one year or one and half a year but also on some internal research products. I have

worked on both types of projects.

3) My projectsI will develop only two project in my report.

3.1) Market product: Developing a whitening day cream3.1.1) introduction to whitening day creamMy goal was to develop a formula of whitening day care for Mexico for a low cost project. Indeed, the brand Nivea wants to develop new products for a largest entry on the market.The whitening creams or lotions are becoming more or more popular in Latin America called “Aclarado”. But the meaning “whitening” is not

exactly the same as in Asia in the mind of people: it is considered more like a protection for the skin, the visage and anti-aging. Competitors have already developed these products on the market with low prices. The main competitor for Latin America is POND‘S which dominates face care due to specific offer with separate shelf placement.

3.1.2)Formulation development: how does it work?

Basis formulas for the beginning

For developing a formula at BDF, you need to have a basis formulation which is already or going on the market. For my project, at the beginning, I have two basis formulas.We have studied some cost reductions by reducing the amount of raw materials which were expensive. Two emollients, dimethicone and silicon were reduced and the sensory properties were checked and compared to the initial formulas. The results were fine.

Benchmarks study

For the following of the project, we have to develop new formulas in parallel with two benchmarks.-Pond´s normal to dry-Pond´s normal to oily.At BDF, there is a department specialized for competitors products. I have studied those two competitors’ products, check the sensory properties, the consistency and compare the Inci name. That´s why, we have followed with only one emulsifier system to be closer to benchmark: Acid Stearic system which is a very stable system.

Pratical skills in the lab

I have developed different formulas based on O/W emulsions.An O/W emulsion is made of a water phase and an oil phase. Both phases have to be heated up

to 80°C. The water phase is added to the oil phase in the kitchen aid. The thickener phase made of carbomers or polymers is dispersed with silicon or dimethicone in a glass and then add to the main phase. If necessary the emulsion is neutralized by sodium hydroxide and following by a hot homogenization.Then, the emulsion is cooling down to 40 degree, where you have the possibility to add some powders.At least, the active and the perfume phase are added at 25°C. At the end, a cold homogenization is made.Annex pictures

Optimization of the formula

To optimize a formula, we have to check and change the amounts of current or new raw materials.a)First of all, I have studied four raw materials for cost reductions: cyclomethicone(emollient),

Hydrogenated Vegetable Oil(;emollient), C12-15 Alkyl Benzoate(emollient)and Tapioca Starch + Eau( powder for mattifier sensory active). I have varied the amount of these raw materials and evalutate the sensory properties of the formulas:

Raw materials(%)/Formula

Basis Formula 1 Formula 2 Formula 3 Formula 4

Cyclomethicone 3 2 1 3 3

Hydrogenated Vegetable Oil

3 2 1 0 0

C12-15 Alkyl 3 2 1 0 0

Benzoate

Tapioca Starch + Eau 3 2 1 0 3

Analysis of the results: The pH, the consistency, the stability and the sensory properties were studied and compared.

Tapioca Starch is necessary in the formulation for the smoothness, the skin feeling, and the fast power of absorption. Indeed, Tapioca is a Natural, non-modified starch,spherical truncated particles, soft, cushion like feel on the skin and has a high purity talc alternative. Hydrogenated Vegetable Oil and C12-15 Alkyl Benzoate can be cancelled because the skin feeling is still fine and the emulsion is less fatty, oily.Cyclomethicone cannot be reduced as a minimum of amount is necessary to disperse the carbomer. Starch Morphology,

Microscop electronic Magnification:2400* National Starch Personal Care

b)Formulation less oily closer to Pond´s normal to dryCera Microcristallina and Paraffinum Liquidum are two emollient which were studied. We

reduced the amount from 2% to 0%. The best result was without any oils and the formula was less heavy. Caprylic/Capric Triglyceride , an emollient too was replaced for costs reasons by Isopropyl Palmitate (IPP JAFA).Both formulations were compared and the sensory properties. However, the formula was still too fatty; that´s why we decided to cancel all the oils in the formulas.Conclusion: the elimination of oils gives a better sensoric, less sticky and waxy, good spreadability, better whitening effect upon the skin and reduce the prices.

c)Carbomers study Carbomer is high molecular weight polymers of acrylic acid used as thickening, dispersing, suspending and emulsifying agents. The typical concentrations used is 0, 3%. Carbomer is used for low flow for creams and lotions. The amount of carbomer tested vary from 0,1% to 0,5%.The amount of cyclomethicone (emollient to disperse it) was also minimized for cost reductions at the same time. The results were good as we could use 0,3% or 0,5% of carbomers dispersed in 1% of cyclomethicone.Conclusion: The combination of 0, 5% of carbomer and 1% of cyclomethicone is the

best solution to reach a consistency like the benchmark “normal to oily”and to keep the same sensory properties.

d)Addition of Silica Dimethyl Silylate to improve the sensory and the consistencySilica Dimethyl Silylate is a silica derivative in which the surface of the fumed silica has been modified by the addition of dimethyl silyl groups Silica Dimethyl Silylate is used as a filler matifier and rheology modifier In my formulation, it is

used for its sensory properties and its capacity to increase the viscosity.

Pyrogenes Silica mit einer

Primärteilchengröße von ca. 7 nm und einer spezifischen Oberfläche von ca. 300 m2/g.)

Different batchs were formulated to optimize the right amount of Silica to use from 0,25% to 1,5%

Results:

% Silica Dimethyl Silylate

Comments Realization in the lab

1,5 Bad results, bad spreadability, agglomeration of particles, not stable

Difficulty with the last homogenization, not pratical with powder

0,75 Too much, bad skin feeling, agglomeration of particles

Difficulty with the last homogenization, not pratical with powder

0,5 Not smooth properties Difficulty to realize0,25 Dry skin feeling, fast absorption, smooth Easy to realize

e) I have studied also the emulsifier systems “Acid Stearic in combination with Cetyl Alcohol and Glyceryl Stearate. Those three raw materials are working together with specials amounts to use which are well known by BDF whereas the emulsion does not work. However, I won´t develop this study in details.

After checking all the sensory properties and the stability, only two basis formulas were choosen among 26 formulas for the next steps.

Stabilty tests:The favorite’s formulas are following by stability steps by steps.The formulas are filled in glass and put on stability at 40°C, at 50°C,RT,-10°C and 6°C for 6 months. 6 months of stability corresponds to 3 years of stability.The samples are also submitted for one week to a processus of temperatures from -10°C to 40°C. Microscop optic *100The pH, the viscosity and the consistency are also checked during these 6 months.The formula is also verified with a microscop optic to check if the

emulsions is stable, if we don´t see any crystals inside.Annex stability tests

3.1.3)Interaction with other departments

I have had the possibility to work with other departments and to understand how a product is built. Marketing collaboration

I have had the possibility to work directly with the marketing to decide the final formulas and the needs of the market.That´s why the formula should be with a light-textured moisturizing, enriched with Aloe Vera and Vitamin C which helps your skin recover its natural tone and increases its brightness. UV filters protect it from sun and further darkening. The marketing department coordinates the interaction between the marketing in Latam America and the research in Hamburg.

Fragnance Management

This department takes care of the fragnances for Nivea product. They work directly with fragnances houses to create the best perfumes and is directly linked to the market. For my project, we had four perfumes at the beginning. After a direct contact with Mexico, we decided to go for 2 perfumes with 2 formulas basis.

Analytic departmentFor testing the stability quickly of one formulation, I have worked with Rheologie and Thermoanalytic department. The method used by BDF is LUMiSizer, an instrument which can characterize of any demixing phenomena, like sedimentation flotation or consolidation and the calculation of the velocity distribution in the centrifugal field.Principe of the Step Technology:12 samples are tested simultaneously. Parallel near infrared or blue light illuminates the entire sample cell and the transmitted light is detected by the detectors. Transmission is converted into extinction and particle concentration may be calculated. Demixing phenomena can be quantified regarding separated phase volume, sedimentation..The samples are submitted to temperature control from -4°C, 60°C.Annex of example Lumifug

Quality departmentBefore beginning any kinds of tests, we need to ask the quality to know which tests we have to do and explain our formulations.

Test Center:Different kinds of tests can be done in collaboration with the test center. A stinging test, a dermatogical test and a PHA for the allergy are commonly done and check in comparison with a benchmark.

Scale process: pilot 20kg or 100kgWhen we change from one scale to other, it is necessary to test our formulations not with only 2 kg but more. A department takes care of this new scale and adapt the formulation without changing the raw materials. The processus is quite similar as in the lab but is more focus on praticals uses. I have realized batches for 15, 20 and 100kg.

MicrobiologyThe samples are analysed for microbiology test. The preservatives in the formulation are evaluated for knowing if they are sufficient or not. The bacteria inside the formula are also counting: -E coli, P putida-C albicans, P aeruginosa, S aureus, A brailiensis.

Packaging compatibility The packaging for one product is as important as the formula. In fact, the packaging could have an impact on the stability of the formulation. A department is specialized for developing new packaking which are compatible with the formulation. The traditional packaging compatibility is to test samples at 40°C, 6°C, 50°C and RT for six months. An other test is to weight the product in the packaging every 2 months for 6 months at RT and 40°C to see if we don´t lose any products.ANNEX Pphoto

Conclusion: the project was really interesting because I have followed it steps by steps from the beginning of my internship to the end. I have had the possibility to understand how a product is created and the different scales to follow. I have developed my knowledges in terms of formulation cosmetics, whitening products and cultures concerning those countries, to be open-minded , to work with other departments.

3.2) Internal research: developing one sunscreen formula for SPF 50 for Latam America and China

3.2.1) Goal of the projectThis project was a real challenge for both countries to get a high SPF.

The difficulty was to develop only one formula for Latam America and Asia.

Indeed, there are a lot of regulations concerning the amount of some raw materials and they are often different from one country to another. My objective was also to use new UV filters, to create new sensory properties and to develop a formula not expensive.

3.2.2) UV filters introductionMy first work was to draw a list of all the sunscreens with high SPF in Europe from Nivea and

Eucerin and to study the UV filters systems.Introduction to sunscreens and UV

Solar radiation in the range of infrared is perceived as heat, in the visible as color, and in the ultraviolet as the result of photobiological reactions. The fact that radiation energy increases with a decrease in wavelength, and that longer wavelengths are less scattered by an object also holds true for UV radiation (UVR). UV filters are compounds which prevent ultraviolet light from coming through. They are used to protect the skin in sunscreen formulation.In consequence, and based on empirical observation, the spectrum of ultraviolet light with a wavelength between 100 nm and 400 nm has been divided into three different ranges: UV-C, UV-B and UV-A.I have studied UV-B and UV-AUV-A (wavelengths between 320 – 400 nm) Annexe:spectrum

UV-A radiation penetrates down to the dermal layers of the skin. It stimulates tanning and pigmentation and relates to skin aging, and skin cancers such as melanoma. UV-A may act in an indirect way by creating free radicals and reactive oxygen species.

UV-B (wavelengths between 290 – 320 nm) UV-B radiation stimulates the production of Vitamin D. It affects especially the epidermal layer of the skin, where it causes erythema (sunburn). Frequent and intense exposure to UV-B induces lesions on the DNA and modulates the immune response of the skin. In turn, UV-B enhances the risk of fatal mutations eventually leading to skin cancer and reduces the chance that a malignantly transformed cell is recognized and destroyed.

3.2.3)Development of the formulas and work on UV filters

3.2.3.1) Objective of the formula:The sunscreen should contain UVA and UVB radiation, providing a high Sun Protection

(SPF), being photostable, having good water resistancy and new sensory properties which are still not on the market. The basis formulas were two creams for Visage with SPF 42 and 37,5. I have studied each UV-filters system. In fact, some UV filters are not compatible for chemical explanations and patents reasons. 3.2.3.2) UV filters used:

UV filters UV Characteristics Amount(%) Comments

Homosalate B oil soluble, liquid 7--9  chemical

Octocrylene B liquid, viscous 2--8Good with UVB,chemical

Ethylhexyl Salicylate B liquid, colourless 4,5  chemicalButyl Methoxydibenzoylmethane A

powder, yellow, solid 2,7 chemical

Phenylbenzimidazole Sulfonic Acid A powder, white 2

be careful with the water resistancy, chemical

Polysilicone-15 Bliquid, viscous, slightly yellow 1

high protection formulas, photostability,chemical

Titanium Dioxide + Trimethoxycaprylylsilane B

white powder, mineral 0,5--4

high level of UV B absorption

Diethylamino Hydroxybenzoyl Hexyl Benzoate A yellowish 0,5  chemical

Benzophenone-3 Blight yellow powder 3  chemical

Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine A+B oil soluble, liquid 0,5

new UV filter system, good for high SPF,chemical

I will develop only a part of the project. I have developed more than 30 formulas by studying the effect of one UV filters step by steps on the formulations. I have varied especially four (mineral or chemical )raw materials used in these formulations: Octocrylene, Polysilicone-15, Titanium Dioxide + Trimethoxycaprylylsilane and Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine.

For each formulas, the stability was studied at each steps ( annex stability ref).The SPF was tested in vivo for 7 formulas.(see paragraphheXXX)

3.2.3.3) Study of four raw materials for the development of formulas

a)Study of OctocryleneThis UV filter promotes more UV-B and less UV-A protection can be used for 1% to 10% of maximum concentrations. I have developed formulas with an amount of octycrylene from 2% to 8%. It is well-known as an excellent solver for solid in suncreen. It is hydrophobic and oil-soluble. It is preferred for water resistant and water repellant formulations. The combination with benzophenone-3 or ethylmethoxycinnamate increases the SPF. Octycrylene has the ability to stabilize other UV filter such Butylmethoxycinnamate

( Losar A).

Conclusion from SPF results: The combination of Octocrylene (Lischu N) and Phenylbenzimidazole Sulfonic Acid has demonstrated a booster filter for high SPF. Octocrylene has shown SPF booster up to 10, can be used in high concentrations and increase the viscosity.

b) Titanium Dioxide + TrimethoxycaprylylsilaneIt is a hydrophobically modified microfine which is easily dispersed in polar emollients and has excellent water resistancy. It provides a high level of UV-B absorption and acts as an SPF booster together with organic UV filters .It has demonstrated high level of photostability.Titanium dioxide could be used from 0,5% to 10%.I have developped formulas with amount from 0,5% to 6%.The results are the following:

% Titanium dioxide

Sensory properties Whitening effect

Preparation in the lab

0,5 Nice feeling, good spreadabiliy Any Easy to manipulate

2 Good skin feeling, good spreadability, Small Whitening

Easy to manipulate

4 Good skin feeling, fast absorption and spreadability on the skin, dry skin feeling

more lightening effect,

Be careful with the powder

6 Bad spreadability, so bad skin feeling. Intense whitening effect

Difficult to use

Microsscop interprationsConclusion: 2 and 4% of titanium dioxide are the best solutions. Indeed, the formulas have a nice skin feeling, not sticky, a lightening effect and a fast

absorption. An amount of 6% or up to 6% need to pay attention because the pigments of the titanium dioxide may penetrate on the skin and leave a white film on the skin.Whitening effect on the skin during the application

c) Polysilicone-15Polysilicone-15 is mineral UV-filter which provides high SPF and photostable sun care products. It is a new product. It has been demonstrated synergistic effect in combination with other UV-Filters. It shows a significantly less whitening during and after spreading compared to microfine TiO2. The concentration used usually is between 1% to 3%. We have developed formulas with only 1% due to the cost of the raw materials.Polysilicone-15 has demonstrated an excellent skin feeling, a fast absorption and very high SPF booster:SPF up to 13.The formula has a good spreadability and non sticky.

d) Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine

This UV filter provides excellent UV-A protection to serve as a basis for UV protective day creams and shows synergistic effects with UV-B filters for high-SPF sunscreens.The molecule is fully conjugated across the triazine center. The asymmetry is responsible for two absorption peaks, one in the UV-B and one in the UV-A range, which results in the broad-spectrum characteristics. It provides also a good photostability.

The amount used is between 0,5% and 3%. We decided to use o 0,5% as it was the first time we used it and for cost reductions. According to the results of SPF, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine is also booster filter: SPF up to 15.The skin feeling is good but the formulas are more richer than with polysilicone-15.

3.2.3.3) Explanations concerning the SPF test:

After a selection of 7 samples among 30 formulas, we calculated the SPF with the sunscreen simulator from BASF. The Sunburn Protection Factor (SPF) is defined as the ratio of the Minimal Erythema Dose of protected skin and unprotected skin .( Annex calculations SPF)This Sunscreen Simulator calculates the Sunburn Protection Factor with two UV sources and at different application amounts. In addition all common UVA indices are determined. But it does not replace the actual formulation work and in vivo SPF testing of the final product. Then, the sunburn protector factor was measured in an institute in vivo on a panel of 10 people.

3.2.3.3) Results and interpretations The results were very good. In fact, we have got very high SPF and the possibility to create a platform for high SPF from 50 to 80+.We have calculated the price of the formulas which was quite good but we try to reduce it by using other powders which are less expensive and demonstrate also nice sensory properties.I won´t develop this point here because it was at the end of my internship.

Perspective:

This project will be use in the future by the labs and the international lab. We need to wait for the complete results of this SPF and to begin the test for UV-A. Then, the platform can be divided in different kinds of products such face care, lotion, light lotion, creams.

CONCLUSION

My internship was very interesting because I have had the possibility to learn a lot in different areas. I have worked on three main projects: the development of sunscreen formulation with high SPF, face care products (gels and emulsions). I have learnt how to manage different projects at the same time. In fact, my time was shared for working on my own projects but also I have helped my colleague for some supports.It was really challenging for me. I have developed my team-working quality, being well-organized and open-minded.

I have built up knowledges concerning the UV filters and their functions in cosmetic formulations. Nowadays, the UV filters are becoming more and more used by formulators even in day cream to protect the skin against the radiation of the UV.The development of the sunscreen formula was my biggest projects and we got very good results of SPF. I have also achieved pratical and theorical knowledges concerning emollients, emulsifiers, thickeners systems and fragnances. II have learnt how to evaluate the sensory properties. This point was really new for me.All on my formulations were evaluated by the stability tests.

The second key learning concerns the creation of a product from the beginning to the end. During my internship I have worked with different departments as marketing, prototyping, quality, formulation management, fragnance management, rheology, microbiology, analytical and the test center. If you want to work in the best conditions and make the best product, you need to discuss, to exchange and to stay in touch with all of these departments. The research and development needs all these departments.

My last learning concerns Innovation as a key of the success. I have been always in touch with my colleagues who has always to develop new formulations which are the more innovated. During my projects, I was directly in touch with innovation because I have to develop new sunscreen formulas with high SPF for Latam America and Asia with new sensory properties, with special characteristics( light formula and not sticky).In fact, a great work in research is done for creating new feeling, new sensory properties and using new raw materials. I have built up learnings about the regions.Especially for Asia and Latam America, you have to stay closer to the market and the culture of those countries. Indeed, men and women have special needs which are not the same as in the international market. That´s why you have to make real innovations.

Annex 1: Organization of the Research Development for the regions

Annex 2: pratical experiments in the lab

Annex 3: Stability tests

Annex 4:example Lumifug 1.2

Parameters RT ;-10°C ;+6°C ;+50°C ;+40°C;-10°C +40°C Sun test

pH × Visco × Stability × × × × × × ×Water separation × × × × × × ×Oil separation × × × × × × ×Discoloration × × × × × × ×Microscop × Deadeline(days) 1,7,30,60,90,180 30,60,90,180 30,60,90,180 30,60,90,180 30,60,90,180 7 4,8,12

Annex 5: example Lumifug 2.2

Annex 6: packaging

Annex 7: Spectrum of the sun

Annex: Penetration of UV on the skin

UVA and UVB absorption:

UVB-Filter Absorptions-Maximum 290 and 320 nm UVA-Filter Absorptions-Maximum 320 and 400 nm

Annex 8: SPF calculations explanations

Annex 9: exemple of BASF Simulator

Annex 10: BASF simulator UVA

Date of the

internship

du 01.07.2010.

au 31.12.2010Stage année de césure :

1ersemestre

Year

2010/2011

De Marco Marine

Spécialité : CGP

RESUME (300 mots en minimum, précisez : objectifs, moyens, résultats,

conclusions, perspectives. Attention ce résumé ne doit pas contenir

d’informations confidentielles)

J´ai effectué mon premier stage d´année de césure de six mois au sein du groupe Beiersdorf a Hambourg en Recherche et Développement pour l´Asie et l´Amerique Latine. J´ai pu travailler sur plusieurs projets, diverses et variés qui m´ont permis d´acquérir de nombreuses connaissances en cosmétiques.

Le premier projet qui m´a éte confié est le développement d´une crème de jour “whitening”. Le but est d´optimiser la création de cette fornule en tenant compte des divers criteres et de la concurrence. J´ai ainsi du choisir le systeme emulsifiant adapté afin de me rapprocher100 des produits compétiteurs et d´optimiser cette formule de base. J´ai ainsi travaillé sur la variation de la quantité de plusieurs matieres premieres dans la formule. Je me suis interessée en particulier a des carbomere, des emollients, des epaississants. Apres comparaison et etudes des proprieties sensorielles d´une vingtaine de formule , nous avons selectionne deux formules ayant des caracteristiques differentes: consistence, brilliante, effet sec .J´ai bien sur suivi la stabilite de ces formules au cours de mon stage.J´ai appris beaucoup concernant les fonctions et l´utilisation des excipients en cosmetiques. J´ai aussi étudier 100l´influence des parfums dans la formule et leur stabilité. Ce projet m´a permis de comprendre la creation d´un produit jusqu´a sa mise sur le marché. Le produit depuis sa creation doit suivre des étapes clés qui sont essentielles pour une enterprise comme Beiersdorf.