Cosmetics and personal care

Natural thickeners are common used in products such as toothpaste, shampoo and creams and lotions to control the rheolog) of the product. In toothpaste for example, CMC, carrageenan and xanthan are used to control the smoothness and gloss of the product. They can also improve the extrusion properties and prevent tailing when the product is squeezed from the tube. Stability is also important and natural thickeners help to maintain the ribbon on the brush and also provide stability to temperature fluctuations. 

In shampoo, natural thickeners such as xanthan gum can be used as a suspending agent for active ingredients such as zinc pyrithione used in anti-dandruff formulations. Xanthan gum is a negatively charged polymer and so care has to be taken with the formulation since it is incompatible with cationic surfactants. Guar gums modified to be cationic are also used and have improved compatibility with the cationic surfactants. 

The excellent water-binding capacity of natural thickeners means that product such as CMC are used as superabsorbents in nappies and female hygiene products. 

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Personal care and cosmetics are important markets for silicones, and have achieved a high degree of market penetration during the last 25 years. Total sales of silicones in the personal care industry are estimated to be between 21 (X)0 and 23 000 tons/y. 

Personal care and cosmetic products In hand lotions (as emollients/demulcents), in toothpaste, in cosmetics, in shampoo and hair conditioning formulations... 

Many personal care and cosmetic products contain toxic chemicals. Categories of products containing toxicants are listed in Table 11.9. 

In addition to those listed in Table 11.9, a large number of the chemicals listed on the FDA GRAS, and EAFUS lists (see Section 10.7) are also contained in personal care and cosmetic products. Cosmetic products in particular have come under close scrutiny in the European Union, which has far more stringent labeling requirements than those in the United States. 

Table 11.9 Personal Care and Cosmetic Products Containing Toxic Chemicals...

Table 11.10 Partial List of Toxic Chemicals Contained in Personal Care and Cosmetic Products...

Mixtures play a large role in personal care and cosmetic product toxici-ties. Several studies illustrate this. 

The Food and Drug Administration (FDA) mandates warnings on labels for foods, personal care, and cosmetic products. These are specifically exempt from regulation by other federal government agencies. 

Several industrial systems involve emulsions, of which the following are worthy of mention. Food emulsions include mayonnaise, salad creams, deserts, and beverages, while personal care and cosmetics emulsions include hand creams, lotions, hair sprays, and sunscreens. Agrochemical emulsions include self-emulsifiable oils that produce emulsions on dilution with water, emulsion concentrates with water as the continuous phase, and crop oil sprays. Pharmaceutical emulsions include anaesthetics (O/W emulsions), hpid emulsions, and double and multiple emulsions, while paints may involve emulsions of alkyd resins and latex. Some dry-cleaning formulations may contain water droplets emulsified in the dry cleaning oil that is necessary to remove soils and clays, while bitumen emulsions are prepared stable in their containers but coalesce to form a uniform fihn of bitumen when apphed with road chippings. In the oil industry, many crude oils (e.g.. North sea oil) contain water droplets that must be removed by coalescence followed by separation. In oil slick dispersion, the oil spilled from tankers must be emulsified and then separated, while the emulsification of waste oils is an important process for pollution control. 

ISEs have been used for the determination of sodium and potassium in bile, nerve and muscle tissue, kidneys, blood plasma, urine, and other body fluids. ISEs are used for the analysis of ions in sea water, river water, and industrial water and wastewater, as well as in a wide variety of commercial products, such as personal care and cosmetic products. The advantages of ISEs are that they are fast, with response times < 1 min for most ISEs they are nondestructive, have a linear range of about six orders of magnitude in concentration, usually over the 10 to 1 M range, and they can be used in turbid or highly colored solutions. The disadvantages are that a different electrode is needed for each ionic species, the electrodes are selective but not specific, so interferences can occur, and the electrodes can become plugged or contaminated by components of the sample. The ionic species must be in solution and in the proper oxidation state to be detected by the electrode. 

Hawkins, S. Wolf, M. Guyard, G. Greenberg, S. Dayan, N. Microcapsnles as a delivery system. Delivery System Handbook for Personal Care and Cosmetic Products, Rosen, M. R. Ed., Norwich, NY William Andrew Pub. 2005, pp. 191-213. 

Many mixtures of surfactants, especially ionic with nonionic, exhibit surface properties significantly better than do those obtained with either component alone. Such synergistic effects greatly improve many technological applications in areas such as emulsion formulations, emulsion polymerization, surface tension reduction, coating operations, personal care and cosmetics products, pharmaceuticals, and petroleum recovery, to name only a few. The use of mixed surfactant systems should always be considered as a method for obtaining optimal performance in any practical surfactant application. 

MAJOR APPLICATIONS Release agents, rubber molds, sealants and gaskets, surfactants, water repellents, adhesives, foam control agents, biomedical devices, personal care and cosmetics, dielectric encapsulation, glass sizing agents, greases, hydraulic fluids, heat transfer fluids, lubricants, fuser oil, masonry protectants, process aids. 

Some of the denaturants in laboratory use ethanol are cyclohexane (1%) isopropyl alcohol ( 5%) diethyl phthalate (1%) toluene (1-2%) 2-butanone (methyl ethyl ketone) (2%) a mixture of 2-butanone and 4-methyl-2-pentanone (methyl isobutyl ketone) (2% and 0.5%, respectively) methanol (5%), designated SDA Formula 3 ethyl acetate and gasoline (5% and 1%, respectively), designated SDA Formula 1 ethyl acetate, 4-methyl-2-poitanone, and gasoline (each at 1%), designated SDA Formula 1-1 ethyl acetate and methanol (1-2% and 3-5%, respectively) 4-methyl-2-pentanone and ko osene (4% and 1%, respectively), designated Formula CDA 19 and isopropyl alcohol and methanol (5% each). Note that many other denatured ethanols (e.g., bitrex and menthol denatured) are available, typically for use in personal care and cosmetic products. 

Chapter 7 discusses the phenomenal range and use of silicone polymers that can be found in nearly every branch of personal care and cosmetic development. The chapter discusses how the polymers are made, essentially from sand, and the nomenclature used to describe the many different types of silicone-based polymers found in the industry. 

Microcapsules are present in a number of personal care and cosmetic products (80). For example, deodorants may contain capsules that release their core contents due to moisture developed because of sweating. Microcapsules are incorporated in various cosmetic creams, powders, and personal cleansing products. Kiyama (81) summarizes the preparation and use of poy(vinyl alcohol) microcapsules in cosmetic products. Miyazawa and co-workers (82) describe the formation of agar capsules designed for cosmetic use. They note that residual glutaraldehyde in capsules with gelatin shells formed by complex coacervation may be an issue for microcapsules intended for cosmetic applications. 

AES (C12-C14/15 2-3 EO) can be considered as the most efficient anionic surfactant in terms of superior detergency power, good tolerance for water hardness, mildness on hands and fibres. The application therefore is wide from household to personal care and cosmetic products. Unfortunately, sulphated alcohol ether sulphates show a limited stability to hydrolysis at high temperatures, and this restricts their use in heavy... 

HNTs have a wide range of applications such as for use in anticancer therapy, for sustained delivery of certain agents, acting as a template or nanoreactor for biocatalyst, use in personal care and cosmetics and even used as environment protective (Ravindra et al. 2012). 

J. O Lenick Jr., and C.W. Buffa, Sihcones, in M. Rosen, ed.. Delivery System Handbook for Personal Care and Cosmetic Products, Technology Applications and Formulations, 1st ed., William Andrew, Inc., pp. 635-740,2005. 

Chapters 12 to 15 deal with some specific applications of surfactants in the following industries personal care and cosmetics, pharmaceuticals, agrochemicals and the food industry. These chapters have been written to illustrate the applications of surfactants, but in some cases the basic phenomena involved are briefly described with reference to the more fundamental chapters. This applied part of the book demonstrates that an understanding of the basic principles should enable the formulation scientist to arrive at the optimum composition using a rational approach. It should also accelerate the development of the formulation and in some cases enable a prediction of the long-term physical stability. 

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