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: Cosmetics are broadly categorized into four types: 1. Skin Cosmetics 2. Hair Cosmetics 3. Nail Cosmetics 4. Cosmetics for hygiene purpose 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. 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: The raw materials involved the formulation of the lipsticks could be as follows: Ingredients The solid components / waxes : (a) The hydrocarbon waxes (b) The mineral waxes (c) Hard waxes Example White bees wax Ozokerite wax, ceresin wax Carnauba wax, candelilla wax, hard paraffin (d) Micro crystalline waxes The liquid components Mineral oils, vegetable oils, castor oils, butylstearate, The softening components Glycol, water, silicon-fluids, IPM (isopropyl maleate) Anhydrous lanoline, lanolin cocoa butter, lecithin, The coloring agents Pearlescent pigments Opacifying agents Perfumeries Miscellaneous agents : petrolatum Carmine, dyestuff stain, pigmented stain, lakes etc. Guanine crystals, bismuth oxychloride Titanium dioxide Rose oil, cinnamon oil, lavender oil etc. (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. 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 molded 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. 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: 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: (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. (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. (iv) Lakes: They are potential pigments of many of the D and C colors. 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 Castor oil (dissolving liquid) Anhydrous lanoline (Emollient) Candelilla wax (hardening agent) Isopropyl myristate (blending agent) White bees wax (stiffening agent) Carnauba wax (provides rigidity) Ozokerite wax (increase melting point) Quantity for 100 g 54 g 11 g 9g 8g 5g 3g 3g Eosin (dye) Lakes (color) Rose flavour (perfume) Tocopherol (antioxidant) Paraben (preservative) 2g 5g q. s q. s q. s Formula 2 Castor oil (dissolving liquid) lanolin (Emollient) Candelilla wax (hardening agent) Carnauba wax (provides rigidity) Ozokerite wax (increase melting point) bees wax (stiffening agent) Isopropyl myristate (blending agent) Halogenated fluorescence (color) Lakes (color) propyl Paraben (preservative) Rose oil (perfume) Rose oil (perfume) Quantity for 100 g 54 g 8g 6g 2.5 g 2.5 g 6g 4g 3g 12 g 0.2 g 0.8 g 0.8 g Formula 3 Castor oil (dissolving liquid) bees wax (stiffening agent) Ozokerite wax (increase melting point) Carnauba wax (provides rigidity) lanolin (covering agent/Emollient) Paraffin(stiffening agent) Isopropyl myristate (blending agent) Cetyl alcohol (co-solvent) Propylene glycol (humectant) Propylene glycol monoricinoleate (humectant) Eosin (dye) Color Rose oil (perfume) Paraben (preservative) Tocopherol (antioxidant) Quantity for 100 g 27 g 20 g 10 g 5.5 g 5g 3g 3g 2g 11 g 4g 2.5 g 10 g q. s q. s 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 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. 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 mound. 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. 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 odor 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 products 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 Color 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.