Textbook of Cosmetic Formulations PDF

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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/325023106 Textbook of Cosmetic Formulations Book · May 2018 CITATIONS READS 21 639,318 3 authors, including: Gaurav Kumar Sharma Jayesh Gadhiya Mewar University Mewar University 89 PUBLICATIONS 94 CITATIONS 7 PUBLICATIONS 26 CITATIONS SEE PROFILE SEE PROFILE All content following this page was uploaded by Jayesh Gadhiya on 08 May 2018. The user has requested enhancement of the downloaded file. Textbook of Cosmetic Formulations Authors Gaurav Kumar Sharma Jayesh Gadiya Meenakshi Dhanawat  Text book of Cosmetic Formulations S.N. Contents Page No. 1. Introduction 3 2. Lipsticks 5 3. Shampoos 16 4. Powders 29 5. Nail lacquers 41 6. Creams 51 7. Toothpastes 67 8. Hair dyes 79 9. References 91 2  Text book of Cosmetic Formulations COSMETICS 1. Introduction Cosmetic is a Greek word which means to 'adorn' (addition of something decorative to a person or a thing). It may be defined as a substance which comes in contact with various parts of the human body like skin, hair, nail, lips, teeth, and mucous membranes etc, Cosmetic substances help in improving or changing the outward show of the body and also masks the odour of the body. It protects the skin and keeps it in good condition. In general, cosmetics are external preparations which are applied on the external parts the body. Even in earlier days, men and women used to decorate their bodies for improvement of appearance. Men used leaves of vegetables and parts of animals whereas women use to wear colored stones and flowers round their neck and wrist. Gradually, they start using colored earth and ointments on their face and body. Even bangles and necklace made of baked earth materials became very common among the people. Eye shadow were made of copper (coloured earth) ore and lamp black (coloured earth) while red colour was used for dyeing of hair. Now days, cosmetics are considered as essential components in life. They not only, attract the people towards it but also impart psychological effects. It has gained popularity in the last 3-4 decades and its use has been increased exponentially both-in males and females. The most popular cosmetics are hair dyes, powders and creams. Examples of Cosmetics: Skin-care creams, powders, lotions, lipsticks, nail polishes, eye and face makeup, deodorants, baby products, hair colourants and sprays etc. Uses: 1. They are used as a cleansing, moisturizing and beautifying agent. 2. They help in enhancing attractiveness of the body. 3. They help in altering the appearance of the body without affecting its functions. 4. Sunscreen products help in protecting the body from UV rays and treating sunburns. 5. Acne, wrinkles, dark circles under eyes and other skin imperfections are treated or repaired by treatment products. 6. Cosmetics help in treating skin infection. Classification: 3  Text book of Cosmetic Formulations Cosmetics are broadly categorized into four types: 1. Skin Cosmetics 2. Hair Cosmetics 3. Nail Cosmetics 4. Cosmetics for hygiene purpose 4  Text book of Cosmetic Formulations 2. Lipsticks Definition: Lipstick may be basically defined as dispersion of the colouring matter in a base consisting of a suitable blend of oils, fats and waxes with suitable perfumes and flavours moulded in the form of sticks to impart attractive gloss and colour, when applied on lips. Lipsticks provide moist appearance to the lips accentuating them and disguising their defects. Fig. 2–1. Lipstick Ideal Characteristics of Good Lipsticks: The ideal requirements for the formation of a good lipstick may be as follows: It should efficiently cover lips with colour and impart a gloss which would last long. It should be able to maintain the intensity of colour without any alteration in the degree of its shade. It should be able to adhere firmly to the lips and should not provide any greasy appearance. It should possess good thixotropic property so as to deposit the colour with minimum pressure. It should show a smear proof coloring effect. It should possess required plasticity and be able to maintain all the properties throughout the storage period. It should not be gritty. It should be easily dried. The stick should possess even firmness and should maintain its strength at varying temperatures up to 55°C. The stick should not dry or crumble easily. The lipstick should possess a pleasant fragrance and a good flavour. Should be safe and non-irritating to the lips. Result in blooming or sweating of the lips. 2.1 Formulation of lipsticks The lipstick base is made by mixing the oils and waxes in varying proportions in order to obtain a desirable viscosity and melting point. Composition: 5  Text book of Cosmetic Formulations The raw materials involved the formulation of the lipsticks could be as follows: Ingredients Example The solid components / waxes : (a) The hydrocarbon waxes White bees wax (b) The mineral waxes Ozokerite wax, ceresine wax (c) Hard waxes Carnauba wax, candelilla wax, hard paraffin (d) Micro crystalline waxes The liquid components Mineral oils, vegetable oils, castor oils, butylstearate, Glycol, water, silicon-fluids, IPM (isopropyl maleate) The softening components Anhydrous lanoline, lanolin cocoa butter, lecithin, petrolatum The coloring agents Carmine, dyestuff stain, pigmented stain, lakes etc. Pearlescent pigments Guanine crystals, bismuth oxychloride Opacifying agents Titanium dioxide Perfumeries Rose oil, cinnamon oil, lavender oil etc. Miscellaneous agents : (a) Preservatives Parabens (b) Antioxidants BHA, BHT, tocopherol etc. (c) Flavouring agents Cinnamoniol, spearmint oil etc. Fig. 2–2. Lipsticks 1. The Solid Components/waxes: the solid components are responsible for the final structure of the product by solidifying the liquid matrix. The materials required for attaining a reasonable body, hardness, melting point and shrinkage necessary for the easy release of the mould are together referred to as natural waxes. 6  Text book of Cosmetic Formulations The solid components of the formulation are mostly natural waxes which may be classified as follows: (a) The hydrocarbon waxes: Example: White bees wax (b) The mineral waxes: Example: Ozokerite, ceresine (c) Hard waxes: Example: Carnauba wax, candelilla wax, hard paraffin etc. (d) Micro crystalline waxes (a) Hydrocarbon Waxes : White Bees wax: It is a so known as the common wax and forms the oily base in the formulation of lipsticks. Source: It is naturally obtained from honey combs of the honey bee Apis mellifera. Melting Point: the ranges between 62 - 65°C. Concentration: It is used in concentrations of about 3-10% of the total formulation. Available Forms: It is available in the form of blocks, pills, slabs and cakes. The commercially available bleached form is widely used. Uses: 1. It forms an important base and is extensively used for entrapping castor oil. 2. It has good plastic property and can be readily deformed when it is warmed. 3. It is used as a traditional stiffening agent for lipsticks. 4. It forms a good base in the formulation of moulded products. Advantages: 1. It is compatible with vegetable minerals and animal waxes. 2. It can be moulded into required form. Disadvantage: When it is used at a concentration of more than 20%, it forms a dull film on the surface of the lips. It is usually mixed along with other waxes such as Ozokerite wax, carnauba wax and candelilla wax. (b) Mineral Waxes: They are not popular and have been replaced by the microcrystalline waxes but still used with the same names. They are: (i) Ozokerite Wax: Source: It is a type of amorphous hydrocarbon obtained naturally, from bituminous products. Melting Points: It is available in various grades with melting point ranging between 56°C 82°C. 7  Text book of Cosmetic Formulations Concentration: It is used in a concentration range of between 5 to 10%. Uses: 1. It is used in order to increase the Melting point of the base. 2. It is also efficient in promoting the formulation of a fine crystalline wax gel and thus ensures the maximum retention of the Oil matrix. 3. It can be easily transformed into required shapes. Advantage: It is easily available in various grades. Disadvantage: It may be subjected to adulteration. (ii) Ceresine Wax: Source: It is also obtained naturally from the bituminous products like the Ozokerite wax. Melting Point: The melting point range is between 60-75°C. Uses: 1. It is used as stiffening agents to provide firmness to the finished product. 2. It is used to increase melting point of the base. (c) The Hard Waxes: These waxes are mainly responsible for the shape and the hardness of the lipsticks. They include the following waxes, (i) Candelilla Wax: Source: It is obtained from Euphorbiaceae plants such a Euphorbia cerifera and Euphorbia antisyphilitica. The extraction involves the immersing of the plant in boiling water containing sulfuric acid and later skimming off the wax that rises to the surface. Melting Point Its melting point ranges between 65°C 75°C. Uses: It is used to increase the hardness and melting point of the product either alone or in combination with carnauba wax. (ii) Carnauba Wax: Source: It is obtained as exudates from the pores of the leaves of the Brazilian wax palm tree Copernicia prunifera. The extraction involves cutting, drying and heating of the leaves. Melting Point: Its melting point ranges between 81 to 90°C. Available Forms: It is available in three colors yellow, gray and brown. It is available in hard forms and soft forms. Uses: 8  Text book of Cosmetic Formulations 1. It is used to provide rigidity to the stick. 2. It is used in modest proportion in order to ensure high melting points. 3. It helps in moulding by shrinking the stick away from the surface of the mould in order to aid easy removal. Disadvantage: It is not miscible with the other waxes and remain as a separate solid phase due to its high melting point. (iii) Hard Paraffin: Source: It may be present as a purified blend of several solid Hydrocarbon bases that are obtained from petroleum. Melting Point: Its melting point ranges between 55°C - 65°C. Uses: 1. It is occasionally used in minor quantities to improve the gloss of the finished products. 2. Imparts rigidity to the product. Disadvantage: It has limited solubility in the castor oil and hence doesn't dissolve and may provide a greasy look. (d) Microcrystalline Waxes: They are the hydrocarbons containing a long carbon chain. Melting Point: They have wide melting points ranging between 60°C to 120°C. Uses: They help in maintaining the crystal structure of the lipstick and hence may prevent the sweating. Disadvantage: They possess low solubility in the castor oil. 2. The Liquid Components: The liquid components are mostly constituted by the oils such as mineral oil, vegetable oil, castor oil, alcohol etc. The properties of the oils should be as follows: (i) It should possess good dissolution properties in order to dissolve all the bromo acids. (ii) It should possess an optimum viscosity range. (iii) It should be colourless, odourless and tasteless. (iv) It should be non-toxic and non-irritating. (v) It should be easily compatible and stable. The most commonly used liquid components may be as follows: 9  Text book of Cosmetic Formulations (a) Mineral Oils: (i) They consist of a blend of hydrocarbons obtained from petroleum source. (ii) They may be avail ale as either light mineral oils or heavy mineral oils. (iii) They are mostly used in order to impart gloss to the product rather than their solvent property. (iv) They are used in concentrations of less than 5% and are not rancid. (b) Vegetable Oils: The vegetable oils used may be sesame oil and olive oil. The vegetable oils provides low solubility towards staining dyes and hence less commonly used. (c) Castor Oil: It is obtained from the seeds of the castor plant, Ricinus communis. It forms a most valuable lipstick base. It may be used in concentration of 40 - 50% of the total formulation. It has high viscosity and good dissolving power. It possesses stability towards oxidation. It is widely compatible with other ingredients. The high viscosity may avoid smearing off of the lipsticks. (d) Butyl Stearates: They are useful for the dispersion of colour though they possess less solubility. They can readily wet the colouring pigments. They are odourless and free from rancidity. (e) Propylene Glycol: It is non-toxic and possesses a sweet taste. It has good wetting property towards high colouring stains. It is always used in combination with other monoesters of propylene glycol. (f) Water: It is not used as a solvent but may be used in minor quantities in order to dissolve the colour. (g) Silicone Fluid: It is mostly used to aid in mould release and prevent the rub-out of the wax. It is used in minor quantities. (h) Isopropyl Maleate (IPM): It is used in concentration of 2.3% to increase lip gloss. It acts as a co-solvent along with mineral oil and helps in increasing lip gloss. 3. The Softening Agents: They are used to increase the spread ability by softening the lipstick. The most commonly used softening agents include. (a) Anhydrous Lanolin: It is also known as wool fat or woolwax. It is used at low concentration of about 0.25% in order to impart gloss, softness, emolliency and protection to the lips. The melting point ranges between 36 - 42°C. (b) Lanolin: It is also referred to as hydrous wool fat. It is used in minor quantities in order to improve the covering properties of the film. It contains 25-30% of water and may result in sticky and greasy products. It aids in the dispersion of colored pigments. 10  Text book of Cosmetic Formulations (c) Lanolin Derivatives: They include ethers, esters and lanolin oils. They are almost none drying and thus provide a non-greasy look to the film. They are also used as blending agents or plasticizers. (d) Cocoa Butter: It was used in the past due to its good emollient property. The usage has been stopped due to rancidity and surface crystallization. It provides oily look on the lips and hence imparts good gloss. (e) Petrolatum: It is a hydrocarbon obtained from petroleum. It is odourless and tasteless. It is added mainly to enhance the gloss. (f) Lecithin: It is used in minor quantities to impart smoothness and emollient effect. It increases the ease of application. 4. Colouring Agents: Colour may be imparted to the lips either by staining the lip with a dye stuff colour or by covering the lips with coloring layers. The colours used in the formulation of lipsticks are of two types: (a) Soluble Colours: They are dye stuff agents which are easily soluble in oil, water and alcohol. (b) Insoluble Colours: They are organic or inorganic pigments which are insoluble. Properties of Colouring Agents: They should impart good opacity to the lips by imparting good colour. They should he easily and uniformly miscible with the oils used. The colours must he certified with the F, D and C grade. They should possess very low content of impurities such as arsenic, lead etc,. The commonly used colourants for lipsticks: (i) Carmine: It was extensively used in the past and is obtained as carminic acid from the cochineal insects by extracting the insects with ammonia. The carminic acid obtained is precipitated with alum and is dried and used. (ii) Dye Stuff Stains: They include eosin dyes and provide a long lasting effect on the lips by retaining the color on the lip cells. They are: (a) Eosin Dye: It is used to impart orange red colour to the lips. (b) Acid Eosin Dye: It has orange colour and may change to intense red colour at acidic pH of 4. But they may to toxic effects such as allergic reactions or cheilitis and hence used alone with bromo acids. (iii) Pigmented Stains: They form dispersion in the solvent base. They may be either organic or inorganic. They are used in combination with metallic lakes in order to improve the intensity of the colour. 11  Text book of Cosmetic Formulations (iv) Lakes: They are potential pigments of many of the D and C colours. They may be adsorbed on the aluminium hydroxides, barium oxides, calcium oxides etc,. Example: Aluminium lakes, barium or calcium lakes, strontium lakes. They are used at concentrations of about 8-10%. 5. Pearlescent Pigments: They are used to impart nacreous or a pearl like appearance to the product when applied on the lips. The natural pearlescent pigments may be guanine crystals obtained from fish scales. Bismuth oxychloride in 70 % castor oil may also provide a lustrous look. 6. Opacifying Agent: It is used for opacifying or whitening of lipsticks. It can also alter the basic shade of the pigment. Various shades can he obtained by, varying the proportions. Example: Titanium Dioxide. 7. Perfumeries: Light floral fragrances can be used in lipsticks. They include rose oil, cinnamon oil, lavender oil etc. The fruity flavours that cover fatty odour of the oily waxes may also be used. They should be tasteless, non-irritating and compatible. 8. Miscellaneous Agents: They include the following: (a) Preservatives: They are used to increase life period of the product by reducing the microbial growth. Though they are anhydrous preparations, preservatives such as methyl paraben and propyl paraben may be commonly used. The concentration of the preservative should not exceed 0.1%. (b) Antioxidants: The ingredients used in the formulation may be susceptible to oxidation. This may result in the degradation of the product. Thus, antioxidants are added in order to prevent oxidation of the ingredients. The commonly used antioxidants are butylated hydroxyl anisole (BHA), butylated hydroxyl toluene (BHT), tocopherol, propyl gallate, butylated hydroxyl quinines etc. (c) Flavouring Agents: They are included in order to impart good flavor to the product. They may include the spearmint oil, cinnamon oil etc. Along with the flavouring agents, sodium saccharin and the ammonium glycyrrhizate may also be used in order to improve the taste. The various formulae for the preparation of lipsticks are as follows: Formula 1 Quantity for 100 g Castor oil (dissolving liquid) 54 g Anhydrous lanoline (Emollient) 11 g Candelilla wax (hardening agent) 9g Isopropyl myristate (blending agent) 8g White bees wax (stiffening agent) 5g Carnauba wax (provides rigidity) 3g Ozokerite wax (increase melting point) 3g 12  Text book of Cosmetic Formulations Eosin (dye) 2g Lakes (color) 5g Rose flavour (perfume) q. s Tocopherol (antioxidant) q. s Paraben (preservative) q. s Formula 2 Quantity for 100 g Castor oil (dissolving liquid) 54 g lanolin (Emollient) 8g Candelilla wax (hardening agent) 6g Carnauba wax (provides rigidity) 2.5 g Ozokerite wax (increase melting point) 2.5 g bees wax (stiffening agent) 6g Isopropyl myristate (blending agent) 4g Halogenated fluorescence (color) 3g Lakes (color) 12 g propyl Paraben (preservative) 0.2 g Rose oil (perfume) 0.8 g Rose oil (perfume) 0.8 g Formula 3 Quantity for 100 g Castor oil (dissolving liquid) 27 g bees wax (stiffening agent) 20 g Ozokerite wax (increase melting point) 10 g Carnauba wax (provides rigidity) 5.5 g lanolin (covering agent/Emollient) 5g Paraffin(stiffening agent) 3g Isopropyl myristate (blending agent) 3g Cetyl alcohol (co-solvent) 2g Propylene glycol (humectant) 11 g Propylene glycol monoricinoleate (humectant) 4g Eosin (dye) 2.5 g Color 10 g Rose oil (perfume) q. s Paraben (preservative) q. s Tocopherol (antioxidant) q. s 2.2 Preparation of lipsticks: Successful preparation of lipstick shades depend upon the adequate dispersion of the lake colours in the lipstick mass. It is advisable to prepare the dispersion of lake colours in castor 13  Text book of Cosmetic Formulations oil. Dispersions are generally prepared by milling about 25% concentrations of lakes in castor oil. Method of Preparation: If a solvent is used for the dissolution of bromo acid, the solution is first prepared and set aside until required. If commercial colour pastes are not being used, then lake colours are first dispersed by mixing with suitable quantity of castor oil. The colour paste obtained is passed through a triple roller mill until it becomes smooth and free from agglomerates and gritty particles. The colour mixture is then mixed with the bromo acid mixture. All the ingredients of the base are identified and arranged in the increasing order of their melting points. This mixture is remilled until it is perfectly smooth. Preservatives and anti-oxidant are dissolved in remaining oil and are added to the mixture. Finally, the perfume is added and the mass is stirred thoroughly, but gently to avoid entrapment of air. Automatic ejection mould is preferred for the large scale production. The mould is lubricated with liquid paraffin or isopropyl myristate before pouring the mass into the mould. It is important to prevent settling down of the coloring mass when the moulds are chilled. Lubrication facilitates easy removal of sticks. 2.3 Evaluation of Lipsticks The evaluation studies are important in order to determine the efficiency, stability and the consistency of the finished product. The evaluation tests for the lipsticks are as follows: 1. Melting Point Determination Test: The determination of melting point is done in order to determine the storage characteristics of the product. The inciting point of lipstick base should be between 60 to 65°C in order to avoid the sensation of friction or dryness during application. The method of determination is known as capillary tube method: (a) In this method, about 50 mg of lipstick is taken and is inserted into a glass capillary tube open at both ends. (b) The capillary tube is ice cooled for about hrs and then placed in a beaker containing hot water and a magnetic stirrer. (c) The temperature at which material starts moving through the capillary is said to be the melting point temperature. (d) Another important parameter is the droop point which determines the temperature at which the product starts oozing out the oil and becomes flattened out. (e) The melting point should be higher than the droop point which determines the safe handling and storage of finished product. 14  Text book of Cosmetic Formulations 2. Breaking Load Point Test: This test is done in order to determine the strength and hardness of the lipstick. In this method, the lipstick is placed hori7ental position I inch from the base and weights with increasing loads are attached to it. the weight at which the lipstick starts breaking, known as the breaking load point. The test shall be carried out in specific condition and at about 25 ° C temperatures. 3. Determination of thixotropic character: This is a test for determining the uniformity in viscosity of base. The instrument used for the determination of thixotropic character is known as the penetrometer. 4. Microbiological tests: The test is carried out in order to determine the extent of contamination either from the raw materials or mould. The test involves the plating of known mass of sample on two different culture media for the growth of microorganism and incubating them for a specific period of time. The extent of contamination can be estimated by counting the number of colonies. 5. Test for rancidity: the oxidation of oil such as castor oil and many other ingredients may result in bad odour and taste and also result in a sticky product. The test for rancidity can be done by using hydrogen peroxide and determining its peroxide number. 6. Test for the Application Force: This is a test to determine the force to be applied during application. In this method, two lipsticks are cut to obtain flat surfaces which are placed one above other. A smooth paper is placed between them which is attached to a dynamometer to determine force required to pull the paper indicates the force application. 7. Storage Stability: This test is done in order to determine the stability of product during storage. 8. Stability to Oxidation: The oxidation characteristics of the finished product are determined in order to check the stability of the product to oxidation. The extent of oxidation can be determined by peroxide number of product after exposure or substance to oxygen for a specific period of time. 9. Determination of Surface Characteristics: the study of surface property of the product is carried out in order to check the formation crystal on the surface or the contamination by microorganism or formation of wrinkles and the exudation of liquid. 10. Determination of Colour dispersion: the test is done in order to determine the uniform dispersion of color particle. The size of the particle is determined by the microscopic studies and it should not be more than 50µ. 3. Shampoos Definition 15  Text book of Cosmetic Formulations A viscous cosmetic preparation with synthetic detergent used for washing hair is called shampoo. Its principle function is to clean the scalp such that it should become free from sebum and foreign substances. Shampoo also makes the hair lustrous and good looking. In olden days detergent soap were used for washing hairs, but nowadays it has been replaced by shampoo.Today shampoo has become an important hair cosmetic for both men and women. However the detergent and other raw materials selected for shampoo preparation should be non toxic to tile scalp, eyes etc. Apart from cleaning, shampoo may also be used for medicinal purpose (i.e., medicated shampoo). After preparation each and every shampoo must be evaluated. Fig. 3–1. Shampoo Properties: It should have optimum viscosity such that it facilitates ease during application. It should have good spreading properties. It should produce sufficient lather after application. It should be able to remove waste material such as debris, soil, sebum, dead cells, salts (due to sweat) etc., from the scalp. It should not form any kind of film on scalp. It should rinse out completely after washing. It should produce lather with both hot and cold water. It should facilitate ease of combing after shampooing. After drying, the hair should not give rough appearance. It should provide lustre to the hair. It should produce good odour both before and after shampooing. It should not produce any kind of irritation or itching to the scalp. It should not support any microbial growth. It should be stable and have a half life of about 2 to 3 years. It should be economical. 3.1 Types of shampoo Various types of shampoos are available and they are classified based on their consistency. They are as follows: 16  Text book of Cosmetic Formulations 1. Clear liquid shampoos 2. Liquid cream shampoos 3. Cream shampoos 4. Gel shampoos 5. Powder shampoos 6. Aerosol shampoos (Foam type) 7. Special shampoos Fig. 3–2. Shampoo and Conditioner 1. Clear Liquid shampoo: These are clear liquid preparations that are most widely used. They are usually made by using detergent of low cloud point. Alkanolamides can also be used in these preparations. Some of these shampoos may be transparent. Formula Quantity for 100 g Triethanolamine lauryl sulphate (surfactant) 50 g Lauricisopropanolamine (foam booster) 2g Perfume, color, preservative q. s Water 48 g 2. Liquid Cream Shampoos: These are called as lotion shampoos which are modification of clear liquid shampoos. Addition of opacifier such as glycerylmonostearate, glycol stearate etc., to the clear liquid shampoo yields liquid cream shampoo. Solubilising agents such as magnesium stearate is also used to dissolve the added opacifier. Formula Quantity for 100 g Triethanolamine lauryl sulphate (surfactant) 35 g Glycerylmonostearate (opacifier) 2g Magnesium stearate (stabilizer) 1g Perfume, color, preservative q. s Water 62 g 3. Cream Shampoos: These shampoos have a paste like consistency and are packed in a collapsible tube. They find great use in hair salons. They are also available in jars with wide mouth. The paste consistency is developed by addition of alkyl sulphates, also Cetyl alcohol is added, which serves as a builder. Formula Quantity for 100 g Sodium lauryl sulphate (surfactant) 38 g Cetyl alcohol (builder) 7g Perfume, color, preservative q. s Water 55 g 17  Text book of Cosmetic Formulations 4. Gel Shampoo: These are transparent and thick usually made by incorporating a gelling agent, (e.g., cellulose).There is great use in hair salons and beauty parlors. The principle ingredient is detergent which can be used either alone or in combination with soap. By altering the proportion of detergent, gel of required consistency can be obtained. Addition of methyl cellulose to clear liquid shampoo and its subsequent thickening also gives rise to gel shampoo. Formula Quantity for 100 g Alkyl dimethyl benzyl ammonium chloride 15 g Triethanolamine lauryl sulphate (surfactant) 28 g Coconut diethanolamide 7g Hydroxyl propyl methyl cellulose 1g Perfume, color, preservative q. s Water 49 g 5. Powder Shampoos: As name suggests, it is available in the form of dry powder, initially it was prepared from dry soaps, but nowadays dry synthetic detergents are used for their preparation. Powder shampoo is prepared where addition of water or other solvent reduces the activity of the components, especially in case of medicated shampoo. Nowadays, these shampoos are not used due to the difficulty experienced in their application. Formula Quantity for 100 g Sodium lauryl sulphate (surfactant) 20 g Sarcoside 5g Sodium bicarbonate 10 g Sodium sulphate 65 g Perfume q. s Another formulation called dry shampoo is also a type of powder shampoo. Initially they are applied on to the head and then removed by the brush. it doesn't involve the use of water. They are usually preferred, when the hair are greasy. This formulation usually includes adsorbents. Formula Quantity for 100 g Starch (adsorbent) 15 g Talc (adsorbent) 45 g Kieselgur (adsorbent) 40 g Perfume q. s 6. Aerosol Shampoos (Foam Type): They are called aerosol shampoos because they are packed in aerosol containers.Their formulation, preparation and packing is complicated as an additional propellant is included. The propellant added must be compatible and should not 18  Text book of Cosmetic Formulations reduce the activity of shampooing ingredients. The container opening is provided with a valve. Shampoo comes out as foam when the valve is pressed.Hence also called as foam type shampoo. Formula Quantity for 100 g Triethanolamine lauryl sulphate (surfactant) 60 g Coconut diethanolamide 2g Propellant 10 g Perfume, color, preservative q. s Water 28 g 7. Special Shampoos: These are the shampoos which are meant for special purpose. They are (a) Medicated Shampoo: These shampoos contain medicinal agents. These agents treat the disorders of the scalp or hair. Examples of medicated shampoos are: Anti-lice shampoo, Anti- dandruff shampoo, Anti-baldness shampoo etc,. The medicinal agent added should not irritate the sebaceous glands. It should not sensitize the scalp. The degree of itching and scaling should also be reduced. Among all, anti dandruff type of medicated shampoo is most widely used. Formula for which is given below: Formula Quantity for 100 g Triethanolamine lauryl sulphate (surfactant) 60 g Thymol (anti dandruff) 0.1 g Camphor (counter irritant) 0.1 g Perfume, color, preservative q. s Water 38.8 g (b) Conditioner Shampoos: These shampoos serve for hair conditioning. Initially they clean the hair (and scalp) and keep them in smooth and lustrous condition. They also prevent sticking of hairs. Conditioner shampoo nowadays is widely used by both men and women. Most of the conditioners are made from Quaternary ammonium compounds. These compounds have the property of reducing electric charges between the hair, as a result hair become lustrous easily manageable. These compounds can also exhibit a bactericidal effect. Formula Quantity for 100 g Stearyl dimethyl benzyl ammonium chloride 5.5g Ethylene glycol monostearate 2g Cetyl alcohol 2.5 g Perfume, preservative q. s Water 90 g 19  Text book of Cosmetic Formulations 3.2 Formulation of shampoo Formula of Shampoo contains the following ingredients: Ingredients Examples 1. Surfactants (a) Anionic Surfactants Alkyl sulphates, alkyl ether sulphate (b) Non- ionic Surfactants Alkanolamides (c) Cationic Surfactants Alkyl amines, alkyl imidazolines (d) Amphoteric surfactant Acyl amino acids 2. Foam booster Monoethanolamides, lauramides DEA, cocamide DEA 3. Germicide and anti-dandruff Banzalkoniumchloride, cetrimide, selenium agent sulphide, cadmium sulphide 4. Conditioning agent Lanolin, egg, amino acids 5. Pearlescent agent 4-methyl-7-diethylamino coumarin, 4-methyl-5,7- dihydrocoumarin 6. Sequestrants EDTA, citric acid, tripohyphosphate 7. Thickeners Alginates, polyvinyl alcohol, methyl cellulose 8. Perfuming agent Herbal fruits or floral fragrance 9. Preservatives p-hydroxyl benzoic acid phenyl mercuric nitrate 10. Colour FD and C dye 1. Surfactants: The main use of surfactant is to cleanse and to produce foam. They are generally categorized into four types. They are: (a) Anionic Surfactants (b) Non-ionic Surfactants (c) Cationic Surfactants (d) Amphoteric Surfactants (a) Anionic Surfactants: These surfactants have good foaming property, hence they are used as principle surfactant. They are considered as main ingredient of shampoo formulation. Examples of Anionic Surfactants: (i) Alkyl Sulphates: When fatty acids are subjected to catalytic reduction, it results in formation of long chain sulphated derivatives called as Alkyl sulphates. (Example: Lauryl sulphate, Myristyl sulphate). A combination of above two compounds is most widely used because they give foam. Sulphates with lauryl chain are widely used when compared to octyl or decyl chain. Previously, sodium lauryl sulphate was used but now triethanolarnine lauryl sulphate is widely used. (ii) Alkyl polyethylene Glycol Sulphates: These anionic surfactants exhibit good cleaning as well good foaming property. They are alkyl ether sulphate which forms water soluble sodium salt. Solubility of this salt is greater than sodium lauryl sulphate, hence also serves as a solvent for non-polar ingredients. Because of low cost, they are widely used by small manufacturers. 20  Text book of Cosmetic Formulations (iii) Alkyl Benzene Sulphonates: These surfactants are most widely used in the preparation of washing powder but not in cosmetics (i.e. shampoo). Because they cause excessive cleaning, this may lead to damage of scalp and hair. They nay also lead to hair fall and skin irritation. Although they have deleterious effects, they are used for cleaning of greasy hair. (iv) α- olefin Sulphate: It is an alkyl sulphonate obtained by sulfonation of linear olefin. It produces an excellent foam and the property of foaming is unaffected by sebum and hard water. It produces mild detergent effect without harming the scalp. It is stable at both acid and basic pH and widely used to prepare low pH shampoo. It has low cloud point hence also used to prepare clear liquid shampoo. Apart from the above, other anionic surfactants such as sulphosuccinates, Acyl lactylases etc, are also used. (b) Non-ionic Surfactant: These are considered as secondary surfactants. They are not used to produce foam but used as foam boosters, viscosity inducers, emulsion stabilizers and opacifiers. This is because they have less foaming power. Even though they have good cleaning property, they are not used as principle surfactant. Examples of Non-ionic Surfactants: (i) Poly Alkoxylated Derivatives: These are ethoxylated alcohols and phenols, block polymers, sorbitol ester (polyethoxylated) and polyglyceryl ethers. These derivatives are obtained when hydrogen (labile) containing hydrophobic compound is subjected to poly- addition reaction with either ethylene or propylene oxide. They are stable at wide range of pH. They have stabilizing, emulsifying, pearlescent and foaming properties. They are available at low cost and cause irritation to eye mucosa. However, they are used as mild detergents and impart a good rinsing property. They can also be used in high concentration. (ii) Fatty Acid alkanolamides: These include monoalkanolamides and diethanolamides etc,. Monoalkanolamides are made from long chain fatly acids (i.e., C14- C16). They are insoluble in water due to their Waxy nature. Hence, they are added directly to detergent solution and dissolved by gentle warming. The detergent solution is made by using principle surfactant to which various ethanolamides are added to serve as. Solubilising Agent: Example: Lauric Monoethanolamide. Viscosity Inducing Agent: Example: Lauric Monoethanolamide Pearlescent and Thickening Agent: Example: Stearic Ethanolamide Softening and Hair Conditioning Agent: Example: Oleic Ethanolamide. Foam Boosters. However the ratio of detergent solution to the monoethanolamide must be 100:15 and above this ratio may be harmful to scalp and hair. Whereas diethanolamides are available as low melting point solids or even as simple liquids. They are used as powerful solublizing agents. They solubilize the shampoo ingredients rapidly and more efficiently compared to monoethanolamides. The shampoos containing high soap content and free ethanolamides (Example: Kritchevsky condensation products) must be used with precautions. 21  Text book of Cosmetic Formulations (iii) Amine Oxides: Amine oxides are obtained by the oxidation of tertiary aliphatic amine with hydrogen peroxide. These compounds possess strong polar linkage between nitrogen and oxygen hence they are also called as polar non-ionic surfactants. They constitutes major group of synthetic surfactants. They are water soluble and compatible with various surfactants. They are added as secondary surfactants because of their conditioning, dam boosting and anti-static property. Coconut and dodecyl dimethylamine oxides are most commonly used for this purpose. (c) Cationic Surfactants: Surfactants that contains positive charge are called as cationic surfactants. They are used as both principle and secondary surfactants. These surfactants are used in low concentrations because they are toxic to eye. Hence, they are considered as secondary surfactants. Apart from the above toxic effect, they also have good foaming and partly cleaning properties. Hence, they are also used as principle surfactants in conditioner shampoos. Examples Cationic Surfactants: (i) Alkylamines: They constitute a major group off, cationic surfactants. They are used in combination with hydrophilic surfactants in order to provide conditioning and anti-static property to the shampoo. However they precipitate when combined with anionic surfactants. Usually they are used in the form of water soluble salts. (ii) Ethoxylated amines: These are nitrogen containing surfactants which are obtained by ethoxylation of long, chain alkylamine. They are waxy in nature with low melting point. Because of their waxy nature; they are also used as viscosity inducer. However their main function is emulsification and hair conditioning. Sometimes, they are also used as foam boosters. Due to their emulsifying property, complete dispersion of various ingredients is achieved. (iii) Alkyl-Betains: These classes of cationic surfactants are obtained from N dimethylglycine. They are readily compatible with majority of surfactants and have following properties. Enhance the efficiency of Foam. Example: Foam Booster. Contain Conditioning and Anti-static Property. Have viscosity inducing property. Possess good stability. Non-irritant to skin and eye. Based on the above properties, Alkyl Betains are considered as secondary surfactant. They are also used as principle surfactant in baby shampoo and are often used combination with ionic surfactants. A part from the above, various other cationic surfactants like imidazolines and morphollrx derivatives, tetra alkyl ammonium salts are also used. (d) Amphoteric Surfactants: The surfactants which possess both cationic and anionic charges with respect to acidic and basic media are called as amphoteric solvents. They form zwitterions when the pH of media is neutral.These agents produces a mild action and show 22  Text book of Cosmetic Formulations compatibility with surfactants.They posses excellent hair conditioning property and hence used as secondary surfactants. Examples Amphoteric Surfactants: (i) Dialkyl Ethylene Diamines: These surfactants are soluble in water and compatible with surfactants. They are used as detergents and to a lesser extent as emulsifier. They are usually prepared as aqueous solution or paste into which remaining shampoo ingredients are added. These agents are combined with anionic surfactants in order to minimize the irritation caused by them.These agents neither enhances nor inhibits the foaming property of the principle surfactant. They are most widely used an anti-irritating agent when anionic compounds are used as principle surfactant. (Anionic surfactants are irritant to eye). These agents also possess conditioner and anti-static property as a result of which the hair becomes smooth and soft.However the pH of the shampoo prepared by using these surfactants must be neutral (i.e., in between 6.5 to 7.5). (ii) N-alkyl Amino Acids: The important compounds of this class are derived from amino acids and asparagine. A compound called N- alkyl-b iminoproperonate is derived from b- amino acid and it exhibits good foaming property, possesses slightly alkaline pH by changing the pH to acidic range the manageability of hair is improved. Whereas, The derivatives of asparagine are well compatible with both anionic and cationic surfactants. It also posses the properties like foaming, cleaning and conditioning. Depending upon the pH, these compounds change their nature i.e., they become zwitterions at pH 6 and at neutral pH, they become amine. Solubility of N-alkyl amino acids is greater than they are in the form of sodium salts, whereas the solubility decreases with zwitter ionic form. The foaming property of these agents decreases with decrease in pH. This is because at low pH they become cationated (i.e., cationic form). These agents are highly stable and sometimes also employed as emulsifiers 2. Foam Boosters: The surfactants used in the preparation also serves as foaming agents. They, form rich lather i.e., foam which is stabilized or strengthened by using a substance called foam boosters. The substances like fatty acid alkanolamides, amine oxides are used. They make the foam dense and it to remain for long duration. Usually they are added in quantity of about 2 to 5%. Fatty acids and fatty alcohols when added in a range of 0.25 to 0.50% concentrations, they also act as foam boosters. 3. Germicide and Anti-dandruff Agents: Germicides are the agents which prevent the growth of micro-organism on the scalp whereas anti-dandruff agents are used to eliminate dandruff from the scalp. Examples of Germicides are: Quaternary ammonium compounds: Example: Benzalkonium Chloride, Cetrimide etc. Examples of Anti-dandruff Agents are: Selenium Sulphide Cadmium Sulphide 23  Text book of Cosmetic Formulations 4. Conditioning Agents: These agents improve the condition of hair. These agents have the property of reducing, electric charges the hair, as a result, hair become lustrous and hence easily manageable. These agents also exhibit a bactericidal effect. They make the hair silky and shiny. Most commonly used conditioning agents are lanolin, oils, herbal extracts, egg, amino acids etc. Among the above; amino acid gives an efficient conditioning effect. 5. Pearlescent Agent: these agents are usually added as adjuvants to the conditioning agents. They improve the conditioning property. Addition of these agents also imparts brightness to hair. They make the preparation transparent or opaque; hence they are also called as opacifying agents. The commonly used pearlescent agents are alkanolamides and coumarins like 4-methyl-7-diethyl amino coumarin, 4-methyl-5, 7-dihydrocoumarin etc. Also alcohols and phosphates improve transparent solubilization. 6. Sequestrants: These are complex forming agents. They form complex with metal ions like calcium and magnesium. Surfactant are liable to form complex with the metals present in water i.e., calcium and magnesium. Hence addition of Sequestrants prevents complex formation between metal and surfactant. The Sequestrant itself forms complex with the metal ions. Thus, it prevents the formation of film on the scalp i.e., the film formed by surfactant and metal ions. The commonly used Sequestrants are EDTA, citric acid etc,. 7. Thickening Agents: These agents are usually added to make the preparation thick i.e. viscous. Such viscous preparation facilitates ease of handling. Also, they prevent wastage during application. Already the addition of various agents, such as surfactants, foam boosters etc make the preparation viscous even though thickening agent is added. Substances like methyl cellulose, alginates polyvinyl alcohol, polyethylene glycol etc are commonly used to adjust the viscosity of a shampoo. 8. Perfumes: Addition of these agents imparts good fragrance to the shampoo. It also neutralizes the undesirable odour of other ingredients of formulation especially surfactants. Nowadays it has become an important factor for consumer satisfaction. The selected perfumes must be such that they should retain good smell for fixed period of time even after shampooing. The added perfumes should not affect the solubility and stability of the preparation. They are usually obtained from natural sources such as flowers, fruits, herbs etc. 9. Preservatives: These agents have the ability to prevent the growth of micro-organisms. They are usually added to maintain the stability of the preparation for a desired period of time. Shampoo is a wet preparation that provides a media for various micro organisms hence addition of preservative is essential. Preservative used should not cause any irritation to the scalp. Para-hydroxybenzoic acid and phenyl mercuric nitrate are commonly used preservatives. 10. Colour: Addition of colour gives pleasant appearance to the preparation. Various FD & C dyes are used for colouring the preparation. The added colour must be water soluble and it should not impart any colour to hair or scalp. 24  Text book of Cosmetic Formulations 3.3 Preparation of shampoo Simple procedure is involved in the preparation of shampoo. Initially only one method available for the preparation of shampoo, but later the basic method was modified in order to obtain different type of shampoo like cream, gel, aerosol etc. General Method for preparation of shampoo: Liquid shampoo is usually prepared by this method which involves the following steps: Initially the detergent is converted into a solution form or a detergent solution ma ho directly obtained from the manufacturer. Take about half of the detergent solution into a separate container. To it, add the total amount of secondary surfactant i.e., alkanolamide. Dissolve the alkanolamide along with stirring. Sometimes, gentle heat is also applied. To the remaining half of the detergent solution add suitable amount of perfuming agent and dissolve it. The perfume solution is then added to the alkanolamide solution. Colour and preservatives are dissolved separately in sufficient volume of water and then added to the main solution. The whole, solution is mixed well by gentle stirring. Excessive stirring may lead to bubble formation. Final volume of the preparation is usually adjusted by the addition of clear sterile waste. This gives clear liquid shampoo. However, When the preparation contains lauryl alcohol ether sulphate. It is required to adjust the viscosity of the shampoo. Viscosity adjustment is done by using an electrolyte solution. Usually, a solution of sodium chloride is added subsequently with constant stirring. Care must be taken to it event the excess addition of sodium chloride. Methods of Preparation: The methods of preparation of various types of shampoos are modification of the above mentioned general method of preparation of shampoos. (a) Preparation of Cream Shampoo: Certain formulae of cream shampoo may include glycol stearate or waxes. Usually, glycol stearate is used as an opacifier and preparation method for such formulae is similar as discussed above. But when wax is included in the formula, the process involves the following steps. Initially, a solution of detergent and water are heated to about 80°C. The wax is heated separately in a container at 80°C which facilitates the melting of wax. Both the solutions are kept at 80°C and mixed uniform mixing by constant and gentle stirring. The solution is allowed to cool to about 40- 45°C. After which the remaining ingredients, such as additives, colours, perfume and preservatives are added. The stirring is continued. 25  Text book of Cosmetic Formulations Finally, under warm conditions, the mixture is transferred into a suitable container and packed. (b) Preparation of Gel Shampoo: The method involved in the preparation of gel shampoo is similar to that of clear liquid shampoo. After preparation, the liquid shampoo is usually treated with a suitable thickening or gelling agent such as hydroxy propyl methyl cellulose, this gives a gel like consistency. Addition of appropriate amount of anionic and amphoteric surfactants also leads to the formation of gels. (c) Preparation of Aerosol Shampoo: This type of shampoo is initially prepared by using (earlier discussed) general method. The prepared shampoo is then incorporated with a suitable propellant. The whole mixture is packed in an aerosol container. The propellant creates a pressure within the container due to which spraying action is achieved and the product (shampoo) is sprayed in the form of foam. Here packing plays an important role and the propellant used should not react with the shampoo. (d) Preparation of Powder Shampoo: Powder shampoo is prepared by simple blending. Here, all the ingredients are taken in a state. They are powdered to suitable degree of fineness. The powdered ingredients are blended by using a suitable blender. Two separate solutions of perfume and colour are prepared by using alcohol or water as solvents. The prepared solutions are then sprayed onto the blended mixture. The wet mixture is dried and packed. Otherwise, the ingredients are internally soaked into the solutions of colour and perfume. Wet mass is dried and then subjected to blending. 3.4 Evaluation of shampoo According to the regulatory authorities each and every batch of shampoos must be evaluated prior to marketing. Evaluation is a measure of activity and safety. It also notifies the toxicity, if nowadays most of the shampoos are prepared, from synthetic detergents, hence evaluation becomes an essential factor. However, there is also a need to evaluate herbal shampoo, since it may contain natural ingredient which are liable to contamination. Shampoos are evaluated for the following aspects. (I) Evaluation of Safety (II) Evaluation of Antimicrobial Property. (I) Evaluation of Safety: Safety is an important aspect which must first and foremost parameter of evaluation. As stated earlier the shampoos are made from synthetic detergents, which are liable to irritate skin, scalp and eye. Hence, it becomes essential to evaluate the safety of a shampoo. Over all, the shampoo must be non-toxic and non-irritative. The safety is usually evaluated it, terms of toxicity i.e., if the preparation is found to be non toxic then it is regarded as safe and vice-versa. However, the toxicity is determined by using “Draize test” which suggests two separate methods for testing skin and eye toxicity respectively. The methods are as follows: 26  Text book of Cosmetic Formulations (a) Skin Toxicity Test: The steps involved in this test are as follows: A set of six albino rabbits are selected. They should weigh about 2 kgs. On the skin of each rabbit, a round patch is made by removing hair. Dilute preparation (8-10%) of shampoo is usually applied onto the patches of a rabbits. The shampoo is allowed to react for a period of 3-4 hours. After that it is removed completely from the skin. After efficient washing, the skin is examined for any adverse reactions such as erythema, edema etc. Based on the results obtained the shampoo is considered as either safe or toxic. Usually, there might be chances of adverse reactions because the shampoo was kept in contact for 4 hours. But usual practice of shampooing in human being is for 10-15 minutes. Alternatively, the skin test is also performed on human being. (b) Eye Toxicity Test: The steps involved in this test are as follows: A set of six adult albino rabbits are selected. They must weigh about 2 kgs. One eye of each rabbit is considered as test eye and another as control eye. To each of the six test eyes of six rabbits, the product (shampoo) is applied. Washing is done after 20 seconds pith 200 ml of tap water. The eyes are rewashed after 5 minutes and then after 24 hours. The control eye are also washed on first day and then after 24 hours. The test eyes are observed at 1, 24, 48 and 72 hours respectively. They are also examined on 7th and 14th day. The product is said to be toxic, if there is a development of iris and corneal lesions which remains for more than 7 days. (II) Evaluation of Antimicrobial Activity: Shampoos are liquid or viscous preparations, they are liable to microbial growth. Hence, preservative is usually added to prevent midi growth.The added preservative should have following properties. It should be non toxic. It should be compatible with other ingredients. It should be effective at low concentration, It should be effective against wide variety of microorganism. However, all the above points are considered prior to the selection of preservative. Evaluation of preservative usually involves the study of antimicrobial activity is generally done by using a method called as "Challenge Study". According to this study, the product is said to be preserved when it does not support microbial growth even after repeated attacks of various micro-organisms. 27  Text book of Cosmetic Formulations Procedure (Challenge Study): Initially an appropriate strain of microorganism is selected and is considered as test organism. Usually the species of Pseudomonas are selected i.e., P aeruginosa, P. Putida etc. A culture of any one of the above test organisms is prepared. The product (shampoo) is then inoculated repeatedly in the culture medium and the studies are carried out for a period of 10 to 12 weeks. The inoculums usually contain 5 lakhs to1 crore micro organisms/ gm of product. Along with the test, control samples are also prepared and reserved for reference. Usually two types of control samples are prepared i.e., one sample with preservative and another without preservative. The test comes to a conclusion only when it has been proven that the product has not supported the microbial growth. 28  Text book of Cosmetic Formulations 4. Powders Definition Powders are considered as one of the important products of skin care preparations. They are used widely by both men and women for face and body care. Various types of powders are body powder, face powders, compacts medicated powders (which are used for prickly heat purposes and preventing microbial growth on the surface of the skin), deodorant powders and foot powders for treatment purposes). Powders have different physical properties when compared to the liquid preparations. They have very fine particle size, which helps in producing large surface area per unit weight. This helps in proper dispersion of powder, which covers the large Fig. 4–1. Powder surface area of the body. Characteristics: It should possess good covering Power in order to hide blemishes present on the skin. Adhesion property should be good, so that it should not blow-off easily from the skin. It should remain on the skin for longer period of time to avoid re-powdering. It should be able to impart matt or peach like appearance to the skin. It should remove the shine present on the skin as well as around the nose. It should possess good absorbent property. It should be able to produce, slip property to the skin for easy spreading by puff without producing any blotches (irregular marks). It should be able to produce transparency effect. 4.1 Formulation of powders Ingredients used in the formulation of powders are properly studied before selection. Their character, role and quality are taken into consideration, as they have effect on the finished product. The ingredients used should be of good quality. Properties: They should not be hard in nature. If the materials are present in crystal form then they should not contain any sharp edges as it may damage the skin. They should have less solubility in water and mixtures of fat. They should be non-toxic in nature. They should be chemically stable, in order to prevent interaction with each other. They should not cause irritation to the skin. 29  Text book of Cosmetic Formulations Ingredients Examples 1. Covering Materials Titanium dioxide, zinc oxide, zinc stearate, kaolin, magnesium stearate and rice starch 2. Adhesive Materials Talc, magnesium and calcium salt of myristic acid, zinc stearate 3. Slip Materials Talc, magnesium stearate, aluminium hydrosilicate 4. Absorbent Materials Colloidal kaolin, starch, bentonite 5. Peach Like Finish Rice starch, maize starch, powdered silk Materials 6. Materials Imparting Gualine, bismuth, oxychloride Frosted-Look 7. Coloring Materials Iron oxide, ultramarine, organic lakes and pigments 8. Perfumes Flowery fragrance or synthetic odour Ingredients used in the formulation are classified based on their functions. They are as follows: 1. Covering Materials: These materials should be able to cover small imperfections, enlarged pores and minor blemishes of the skin. The covering power of powder is high, when its surface area is more..This can be achieved if the particles are in finely divided form. Medium in which these covering materials are dispersed plays an important role for imparting efficiency. Dry skin offers better covering power compared to moist skin. Examples: (a) Titanium Dioxide: It is considered as the best covering agent who is widely used in the formulation of face powders. It is inert in nature. It has 1.6 times more covering power on dry skin and 2.5 times more covering power on moist and greasy skin compared to zinc oxide; however it has less sunscreen property. (b) Zinc Oxide: It is also a good covering agent with good sunscreen property because zinc oxide has protective effect against ultraviolet rays. It consist of fine particles, which impart better covering power. But if the particle size is below 0.25 gm, then the covering power is reduced. And in case of moist and oily environment, of zinc oxide covering power is less i.e,. 37% compared to dry powders. Others materials which have less covering power are kaolin, zinc stearate, magnesium stearate and rice starch. They are used in combination to obtain products of different covering ability. 2. Adhesive Materials: Adhesive materials are essential as they are helpful in imparting adhesion i.e., it cling the powder materials not only to the surface of the skin but also to the powder puff. The adhesion of powder to the puff is necessary to take the powder out of the container in case of compact powders. Example: Magnesium and zinc Stearate: Magnesium stearate is more preferred in the formulation of face powders in 3-10% and it has more adhesive property compared to zinc stearate.Whereas zinc stearate is used in the formulation of talcum powders. 30  Text book of Cosmetic Formulations Good quality of magnesium and zinc stearate is used because they provide excellent colour texture with minimum odour and also helps in provide velvety softness to the final product. These materials are water proof in nature. This helps in maintaining the complexion impact even in damp weather. Other materials are lithium stearate, calcium stearate, talc, cetylalcohol (1-2%), stearyl alcohol, glyceryl monostearate, petrolatum, lanolin, and magnesium as well as calcium salts of myristic acid. 3. Slip Materials: Slip character helps in easy application and spreading of the powder on the skin, which in turn provide smoothness to the skin. Example: (a) Talc: it is a purified hydrated magnesium silicate. Formula: H2Mg3 (SiO3)4 or Mg3Si4O10 (OH) 2 It is widely used in the formulation of face powders. It helps in imparting slip character along with softness. It is neutral and cannot absorb water. (b) Aluminium hydrosilicate: It is considered as the basic material for the formulation of powders. It is smooth, fatty and non-toxic in nature. It is prepared by treating acid and then washing with water. Finally drying is carried out. It also produces cooling effect. It also absorbs fatty secretions and water (in small quantity). Other materials are zinc stearate, magnesium stearate, zinc undecanate and magnesium undecanate. 4. Absorbent Materials: these materials should be able to eliminate shine from the skin surface by absorbing the secretion of the skin i.e., sebum and perspiration (sweat). Examples: (a) Colloidal Kaolin: It is fine, white colour powder, which is soft in nature. It is non-toxic and inert in nature. It does not cause irritation to the skin. It absorbs aqueous and fatty substances which show that it has good absorbing capacity. It has good covering power along with less slip property. (b) Bentonite or Aluminium Silicate: It is fine, whitish-grey powder. 31  Text book of Cosmetic Formulations It has good swelling power i.e., can swells up to 12 times of its own volume. It is not widely used in cosmetics. (c) Magnesium Carbonate: It has good absorbing capacity for water and fatty substances. It is less alkaline in nature. Covering power and adhesive property are more, which all the perfume oil to be added first in magnesium carbonate and then mixed with other materials. (d) Calcium Carbonate: It is fine, white coloured powder, which is soft in nature. It has properties similar to that of magnesium carbonate. It is less preferred, as it undergoes alkaline reaction pith skin. Other materials are rice, wheat, corn, potato etc., which have both absorbing and swelling properties. These materials impart sticky character and are non-toxic in nature. 5. Peach-like Finish Materials: These materials help in imparting peach-like finish appearance, which provide bloom to the skin. Examples: (a) Rice Starch: Other starches are also used like maize starch. They are used after drying (i.e., few hours) in order to get better effect. (b) Silica: it is finely divided material which imparts fluffy appearance to the skin. (c) Powdered Silk: This material is obtained from silk proteins. These proteins are subjected to the process of partial hydrolysis which produces hydrolysate. This hydrolysate is grounded to obtain fine powder. They are used in 30% quantity. 6. Materials imparting Frosted-look: This material is capable of producing translucent lustre and shiny look to the skin. It also imparts pearlescence. Example: Guanine (It is not widely used because it is expensive), bismuth oxychloride, mica, aluminium, bronze. 7. Colouring Materials: These materials are mainly used in the formulation of face powders and compacts in order I impart colour. Examples: (a) Iron Oxide: It is an inorganic pigment, which is used for imparting yellow, red and brown colour. (b) Ultramarine: This material is used to impart green and blue colour. (c) Organic Lakes and Pigments: These materials are capable of producing better brilliance the skin. They should not bleed (i.e., loss of colour) in oil and water solvents. 32  Text book of Cosmetic Formulations 8. Perfumes: Flowery fragrance or synthetic odour are used in the formulation of powders. Perfumes should be compatible with the other ingredients in the formulation. Otherwise, the perfume character will change. 4.2 Classification of powders Three different types of powder products are used in cosmetics, which are as follows: 1. Face powders 2. Compacts 3. Body powders / Talcum powders / Dusting powders. Fig. 4–2. Baby Powder 1. Face Powders: These powders have the ability to complement the skin colour by providing velvety finish to it. Properties: It should impart smooth finish to the skin. It should mask minor imperfections (which are visible) on the skin. It should eliminate shine present on the skin due to moisture or grease. It should have long lasting property to avoid frequent application. It should be resistant to the secretions of the skin i.e., sebaceous and perspiration. It should serve as a vehicle to perfumes so that the particles of perfumes may spread easily. A single substance is unable to impart all the characters i.e., covering power. Slip character absorbent capacity, adhesive property. Hence, mixture of substances is used in the formulation of powders to impart desired properties to the skin. Depending on the type of skin to be powdered, the face powders are classified into 3 types. Formula Quantity for 100 g Talc (slip character) 63 g Kaolin (covering materials) 20 g Calcium carbonate (absorbent) 5g zinc oxide (covering materials) 5g zinc stearate (slip character) 5g Magnesium carbonate (absorbent) 1g Color 0.5 g Perfume (odour) 0.5 g 33  Text book of Cosmetic Formulations They are light type, medium type and heavy type. (i) Light Type: These types of powders are applied on dry skin. They have low covering power since the dry skin does not secrete any oils. Large amount of talc will be present in the formulation of powders. Method: It is a dry mixing method. Perfume is added to some part of calcium carbonate, which is absorbent and mixed thoroughly. This preparation is kept aside for some time. This is mixture A. Color is add added to some part-of talc and mixed thoroughly. This is mixture B. Then kaolin, zinc oxide, zinc stearate, magnesium carbonate and remaining part of calcium carbonate and talc are added to mixture B and mixed properly. Mixture A is added to the above mixture and mixing is carried out. Finally, the preparation is sieved by using either a silk mesh or nylon cloth. (ii) Medium type: Type of powders is applied on the normal or moderate oily skins. These skins are shiny in nature due to the sebaceous secretions or perspiration (sweat). They have good covering power compared to light type. They contain less quantity of talc along with slightly more quantity of zinc oxide (The less quantity of talc is balanced by zinc oxide). Formula Quantity for 100 g Talc (slip character) 39.7 g Kaolin (covering materials) 39.5 g Calcium carbonate (absorbent) 5 g zinc oxide (covering materials) 7 g zinc stearate (slip character) 7 g Magnesium carbonate (absorbent) 1g Color 0.2 g Perfume (odour) 0.6 g Method The method is same as that of light type of face powders. (iii) Heavy type: These types of powders are applied on extremely oily skins, which have more shine due to secretions. They have high covering power, in order to cover the shine of the skin. They, contain less quantity of talc and more quantity of zinc oxide. Formula Quantity for 100 g magnesium stearate (covering materials) 5g Kaolin (covering materials) 20 g zinc oxide (covering materials) 15 g Calcium carbonate (absorbent) 39 g Talc (slip character) 20 g 34  Text book of Cosmetic Formulations 2. Compacts: loose powder or dry powders are compressed in the form of cake along with binder by compaction process; in order to form compact Powders. Compact are applied on the face with help of powder puff. The pressure used in compaction process is an important factor in the formulation of compacts. As low pressure may form cake which break easily during use and high pressure form very hard cake which will not adhere to the puff easily. The average particle in compact powders is looser compared tri loose powders, due to compaction. Ingredients: The composition of compact powder is similar to face powder but binding agents e incorporated, in order to increase adhesion property. Binders Examples 1.Dry binders (requires increased pressure zinc stearate, magnesium stearate for Compaction) 2.Oil binder mineral oil, isopropyl myristate, lanolin derivatives 3. Water-soluble binders tragacanth, karaya, Arabic (a) Aqueous solution gums polyvinyl pyrrolidine (PVP),methyl (b) Aqueous solution of synthetic or Semi cellulose synthetic gums Carboxy methyl cellulose (CMC) (c ) Preservatives are added along with gum to avoid microbial growth 4. Water-repellant binder. Mineral oil, fatty esters, derivatives of lanolin. Wetting agent is also used for uniform (These materials are used in combination with distribution of moisture water) 5. Emulsion binder Triethanolamine stearate, non-ionic emulsifiers, glycerol Monostearate. Preparation of Compacts: Compact powders are prepared by three methods. They are: (a) Wet Method (b) Dry Method (c) Damp Method, (a) Wet Method: The basic material (i.e., powder), colour and binders are formulated in the form of paste with the help of water. Then the pastes are pressed into moulds and slowly the products are dried by air. This method is not widely used, as there is a possibility of producing cracks and other faults in the preparation. 35  Text book of Cosmetic Formulations (b) Dry Method: In this method, the basic materials and binders are compressed in special presses with the help of pressure. This method is carried out under controlled conditions. Examples: Mixture of ammonia, stearic acid and starch. Mixture of stearic acid and starch Mixture of sodium stearate, lanolin and cetyl alcohol or Mixture of triethanolamine stearate, lanolin and cetyl alcohol. (c) Damp Method: This method is most widely used for commercial purposes. The base powder, colour and perfume are properly mixed to form a mixture. Then liquid binder i.e., aqueous mucilage or mucin rich emulsion (oil-in-water type) are added to the mixture. Then it is properly blended until the desired plasticity of the product is obtained. Screening of mixture is carried out followed by compression by machine. Finally, the product is dried at elevated temperature. Formula 1 (Without Binder) Quantity for 100 g Talc (slip character) 69 g Kaolin (covering materials) 18 g Titanium dioxide (covering materials) 8g zinc stearate (slip character) 5g Color q. s Perfume (odour) q. s Binder (with Binder) q. s gum Arabic ( water-soluble Binder) 1g Glycerol (emulsion Binder) 5g Water (vehicle) 94 g Preservatives q. s Formula 2 (Without Binder) Quantity for 100 g Talc (slip character) 79 g Calcium carbonate (absorbent) 9g zinc oxide (covering materials) 7g c (slip character) 5g Color q. s Perfume (odour) q. s Binder (with Binder) q. s Gum tragacanth ( water-soluble Binder) 2g Glycerol monostearate (emulsion Binder) 6g Mineral oil (oil binder) 4g Sorbitol 5g Water (vehicle) 83 g Preservatives q. s 36  Text book of Cosmetic Formulations Method: The method is same as that of face powder but here binders are incorporated in the formulation. 3. Body powder/ talcum powder/ dust powders: These powders are most widely used preparation for multiple purposes. They contain covering materials, adhesives, absorbency material, antiseptic and perfumes. The main function of body powder is absorption of perspiration (sweat). Due to the presence of fat film in the body powder, they adhere to the surface of the skin. Fig. 4–3. Talcum Powder Properties: They should provide good slip character to the skin. They should provide cooling and lubrication effect to the skin. They should be able to prevent irritation of the skin. Ingredients: Ingredients which are used in the formulation of body powders are as follows: Ingredients Example 1. Metallic compound zinc stearate, aluminium stearate, magnesium carbonate(light), precipitate calcium carbonate (chalk) 2. Antiseptic materials Boric acid, chlorohexidine diacetate, They are incorporated in the formulation in bithional order to prevent the growth of microorganism which are responsible for the development of perspiration (sweat) and odour. 3. Adsorbent material Kaolin, magnesium carbonate, precipitate chalk, starch 4. Slip character Talc, zinc stearate 5. Adhesive materials Kaolin, zinc oxide, magnesium stearate Formula Quantity for 100 g Talc (slip character) 75 g Colloidal kaolin (adhesive material) 10 g Colloidal silica (binding agent) 5g Magnesium carbonate (absorbent) 5g Aluminium stearate 4g Boric acid (antiseptic) 0.3 g Perfume (odour) 0.7 g 37  Text book of Cosmetic Formulations Method: Initially perfume is mixed with magnesium carbonate (absorbent) properly. This mixture is kept aside for some time. This is mixture A. Talc, colloidal kaolin, colloidal silica, aluminium stearate and boric acid are mixed together. This is mixture B. Mixture A is added to mixture B and then mixing is carried out properly. Then the preparation is passed through a sieve. Finally, the product is packed in a suitable container. Formulation: Formula Quantity for 100 g Talc (slip character) 70 g Calcium carbonate (absorbent) 25 g Zinc stearate (slip character) 4g Boric acid (antiseptic) 0.3 g Perfume oil (odour) 0.7 g Method: Perfume oil is mixed with calcium carbonate (absorbent) properly. This mixture is kept aside for some time. This is mixture A. Talc, zinc stearate and boric acid are mixed together. This is mixture B. Mixture A is added to mixture B and then mixing is carried out properly. Then the preparation is passed through a sieve. Finally, the product is packed in a suitable container. 4.3 Evaluation of powders Evaluation is carried out in order to know the quality of the finished product. General tests include determination of contents in the formulation along with the stability test. This is carried out to know whether the product remains stable for prolonged period of time (i.e.1 shelf life). Other tests are also carried out. They are: 1. Shade Test 2. Colour Dispersion Test 3. Pay-off Test 4 Pressure Test 5. Breakage Test 6. Flow Property Test 7. Particle Size Determination 38  Text book of Cosmetic Formulations 8. Abrasive Character 9. Moisture Content 1. Shade Test: In this test, the variations of colour shade is determined and controlled. It is carried out by spreading the powder sample on a white paper and appearance is observed which is compared with the standard one. Another method involves, applying powder sample and standard one with the help of puff on the skin and then comparing it. The puff used to perform this test is also used for the final product. Evaluation of colour is carried out by using artificial light. 2. Colour Dispersion Test: in this test, a sample of powder is spread on a white paper and with the help of magnifying glass., segregation or bleeding of the colour is observed. the colour should be properly distributed in the powder base of the formulation. 3. Pay-off Test: This test is carried out to check the adhesive property of powders with the puff. This test is mainly carried out on compact powders. 4. Pressure Test: For compaction purpose in compact powders, pressure required. Uniform pressure should be applied to avoid formation of air pockets, which will lead to either breaking or cracking of compact powders. This is because low pressure will make the compact powder soft, whereas high pressure will lead to formation of hard cake. With the help of penetrometer, uniformity of hardness of the cake is checked. This is done by taking the reading at different points on compact powder and then comparing them. 5. Breakage Test: In this test, compact powders are allowed to fall on a wooden surface from a height of about 8-10 inches. This is carried out several times and then checking is done to see whether any breakage has occurred on compact powder. If the compact powder remains unbroken, then it shows the resistance to travel and normal handling by the users. 6. Flow Property Test: This test is carried out maim} on body powders to determine their flow property (from the container upon usage). This intern helps in easy application of powder to skin. In this method, angle of repose of powder is measured by allowing the powder product to fall on a plate through a funnel. Then the height and the radius of heap formed is measured, and even the time taken for the powder to fall is noted. 7. Particle Size Determination: With the help of microscope, sieve analysis or by utilizing other techniques and instrument, particle size of powder product is determined. 8. Abrasive Character: Abrasive character of powder can be determined by, rubbing, the powder on a smooth surface of the skin. Then with the help of a microscope, the effects of powder are studied. 9. Moisture Content: Moisture content present in the powder can be determined by using following formula. 39  Text book of Cosmetic Formulations Moisture Content % = Weight of water in sample × 5 Weight of dry sample This is usually carried out by using various suitable analytical methods. These methods are also suitable for determining limits for colour. 40  Text book of Cosmetic Formulations 5. Nail Lacquers Definition: Nail lacquers or nail paints may be defined as viscous or semi-liquid preparations that are intended for the decoration of the nails of the fingers and toes. Nail lacquers form the most commonly used the most popular type of manicure preparations. Nail polishes are quite distinct from those of nail lacquers and are regarded as a type of manicure preparations that produce a gloss by means of huffing action. The action is mainly by causing abrasion on the surface of the nail and secondly by drawing more blood into the capillaries of the nail. Fig. 5–1. Nail lacquers Ideal Properties of Nail Lacquer: The ideal properties of a nail lacquer should be as follows: It should be safe for the skin and nails and should not lead to any harmful effects. It should be easy to apply and easy to remove. It shall maintain its properties even during long storage. Hence, an efficient nail lacquer should possess consistent stability. The most important property is that it should form a uniform and satisfactory film on the nails. It should have good wetting and flow properties and should be viscous in nature in order to form an appropriate film. The distribution of the colour should be uniform which can be achieved by using finely divided pigments that are uniformly ground and evenly wetted by the solvent. It should provide a good shine on the nail on application. It should possess sufficient adhesive property so that it may uniformly adhere to the nail without slipping. It should possess the required flexibility so that it may not become brittle and crack upon application. The surface should be sufficiently hard in order to prevent th6 effect of impact and scratch. The drying time of the film should not be too rapid or too slow; say about - minutes without forming any bloom. It should be able to preserve all these properties at least for a week after its application. 41  Text book of Cosmetic Formulations 5.1 Formulation of nail lacquers The formation of an efficient nail polish may be based on the selection of a proper and an essential ingredient. The ingredients involved in the formation of a good variety of nail polish could be as follows: S.N. Ingredients Example 1 Film forming agents Nitro cellulose, ethyl cellulose, vinyl polymers 2 Resinous substances Aryl sulphonamide-formaldehyde 3 Dissolving solvent Ether, ethyl acetate, amyl acetate, butyl acetate 4 Dissolving solvent/co-solvent Ethyl alcohol, butyl alcohol 5 Plasticizing agents d-butyl phthalate, n-butyl stearate 6 Coloring agent 5% titanium dioxide (TiQ2) 7 Nacreous/pearly pigments Guanine crystal 8 Miscellaneous substances (1) suspending agent (2) perfumeries Fig. 5–2. Nail lacquers 1. Film Forming Agents: The selection of a film forming agent is an important step in the formation of a relevant type of nail lacquer. The most commonly used film forming substance is nitrocellulose, due to the following properties. The films formed using nitrocellulose pigment stay flexible for a sufficient period of time. It has good adherent property and hence does not allow any chipping and peeling. Its solvent retaining capacity is very low. 42  Text book of Cosmetic Formulations The films formed by nitrocellulose are impermeable to water and air and hence fungal infections can be eliminated. It imparts relevant transparency to the nail enamel. When compared to other film forming agents it is quite hard, tough and has good abrasion resistance ability. Other Film Forming Substances: Several grades of nitrocellulose are available with varying viscosities but only low viscosity grades are used for the preparation of nail polishes. The degree of polymerization determines the viscosity which is necessary in order to prepare a nail polish of required consistency. Two types of grades of nitrocellulose are readily used for nail polish preparation. They may be 'RS' and ‘SS’ type. The most common used type is 'RS' grade with viscosity range 0.25 to0.5 cps. When nitrocellulose is used alone it produces a poor gloss and hence in order to avoid this resins are added. 2. Resinous Substances: Resins enhance the glossy nature of the nail polish and also impart adhesive property. Natural resins such as benzoin, shellac, damar, sandarac and ester gums were used initially but have been replaced' by synthetic resins as they provide good gloss, better adhesion and also increased water resistance capacity. The most commonly used synthetic resin is sulphonamides-formaldehyde resin. it is a polymer made by mixing equimolar proportions of formaldehyde and para toluene sulphonamide. The two commercial types of aryl-sulphonamide-formaldehyde forms are santolite MHP and santolite MS 80 percent. The santolite MHP forms a harder film and the santolite MS 80% provides good gloss, flexibility and now property. But the resin combination is known to cause certain allergic reactions and hence it has now been replaced by other synthetic resins such as polystyrene, polyvinyl polyacrylic ester. Acrylic esters are compatible with nitrocellulose and they provide excellent gloss, adhesion, durability, good flexibility etc. 3. Solvent System: The solvents normally used for preparation of nail polishes may be volatile organic liquids that can dissolve all the ingredients and make a homogenous and uniform preparation. The solvent should be volatile enough in order to leave a continuous, impermeable and hard film but the evaporation should not be too rapid. The selection of a solvent plays an important role in order to provide a balanced rate of evaporation. Generally a mixture of solvents is preferred rather than a single solvent. The solvents used for the formation of nail polishes are of the following types. (a) Low Boiling Solvents: They include the solvents having boiling p