Shampoos and Conditioners

The principles outlined in Section 3.6.6 apply to both the removal and anti-redeposi-tion of soils, and to detergency in both industrial and personal care situations. There are, however, some differences between the application of detergency in an industrial setting (Section 12.2.1) and in a household setting. For example, whereas industrial cleaning usually involves hard surfaces that cannot mechanically hold soil, fabrics can hold soil mechanically, even after the soil has been removed from the fibre surfaces. In addition, fabrics can usually swell in aqueous solution, are permeable to small molecules, and may contain charged or polar surface groups that can interact with soil. An effective shampoo or skin cleaner needs to displace dirt and keep it dispersed so it does not redeposit before the hair or skin can be rinsed. 

Hydrocarbon dirt to be Concentration SDS in water 7d/w Fs/w 7s/d ws/D Removal or non-removal 

Emulsions, Foams, Suspensions, and Aerosols Microscience and Applications, 

Antiredeposition agents. Components in the formulation that act to help prevent redeposition of dispersed dirt or grease. An example is carboxymethyl cellulose. 

Builders. Chemical compounds added to the formulation to aid oil emulsification (by raising pH and to complex and solubilize hardness ions). An example is sodium tripolyphosphate. 

Enzymes. Enzymes such as amylase, protease or lipase are sometimes added to the formulation to increase the effectiveness of the primary surfactant s detergent action, enabling the use of a lower concentration and/or less effective primary surfactant than would otherwise be required. 

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Stearyl alcohol is a nonionic surfactant used as a hair coating in shampoos and conditioners. 

Because panthenol binds well to hair follicles and attracts moisture from the air, it is a moisturizing agent used in shampoos and conditioners. It lubricates the hair without feeling greasy. Instead, it smoothes roughened hair surfaces, making them shiny and easier to comb. 

There are many additives in shampoos and conditioners that appear to be there mainly for marketing purposes. Honey, various herb extracts, and other compounds might add to the fragrance, but they are unlikely to have any other effects in the small concentrations used. Amino acids can act as conditioners, but the source of the amino acid is not important. Silk amino acids are essentially no different from soy amino acids. 

Washing removes the natural coating of protective oil that gives hair its body and shine. To counter this, shampoos and conditioners contain hydrophobic oils that cling to the surface of hair and remain in place upon rinsing. Dimethicone, shown in our inset, is an artificial oil that contains hydrophobic silicon-oxygen chains and methyl groups. 

Therefore, most shampoos and conditioners are slightly acidic. In acidic solutions, the cuticle shrinks and hardens. This smoothes the raised cuticle cells and causes them to lie flatter. Smooth cuticle cells lead to hair that is less tangled and shinier. 

Substantivity refers to the ability of a perfume or a perfume material, applied in a diluted dispersion in water, to attach itself to a solid surface such as the skin (in the case of toilet soap and bath and shower products), the hair (in shampoos and conditioners), or textile fibers (in detergents and fabric softeners). It may refer also to their ability to stay on the surface when this is moistened (as in deodorants or water-proof sun protection products). 

C.I. Basic dyes such as Yellow 57, Red 76, Blue 99, Brown 16, and Brown 17 have been used in color refreshener shampoos and conditioners. Similarly, C.I. Acid dyes such as Yellow 3, Orange 7, Red 33, Violet 43, and... 

Protein hydrolysates are added to hair-care products, such as shampoos and conditioners, and are supposed to repair damaged hair. Hydrolysed proteins are also used in other body-care products, for example soaps, bath gels, and creams. 

Seabuckthorn International (seabuckthorn.com)—cleansing bars, shampoo and conditioner, fruit extract, pulp and seed oil capsules and dispensers, skin cream, lip balm and gloss, tea... 

C. Other Common Auxiliary Ingredients in Shampoos and Conditioners... 394... 

In formulating shampoos and conditioners to provide the above benefits, several unique factors must be considered. The products must act quickly, of the order of minutes, and at relatively low temperatures between 20 and 40°C. The viscosity of the formulations must also be sufficiently high to avoid runoff from the hand while still spreading easily on the hair. In addition, a shampoo must generate a rich and stable lather that can be rinsed easily. Finally, since shampoos and conditioners will be used in contact with skin and eyes, they must exhibit low toxicity and irritation. 

In this chapter the effects of these and other factors on product form and development are discussed. The first section describes general shampoo and hair conditioner compositions. Subsequent sections then discuss hair-cleaning mechanisms and product performance and efficacy, followed by methods of evaluating the cosmetic attributers of shampoos and conditioners. Finally, a brief discussion of damage to hair from shampooing and grooming is presented. 

Polymeric gums are also important compounds for building viscosity in shampoos and conditioners. They are easily dispersed in water at common use levels of 0.5 to 1.5%. The most commonly used cellulose polymer is hydroxyethycellu-lose, which is compatible with anionic and cationic surfactants and stable over a wide pH range [24], Other cellulose polymers in use include methylcellulose and hydroxypropylmethylcellulose. 

It should be noted that the use of different thickening agents in shampoos and conditioners can result in varying rheological characteristics, which affects the choice of a particular thickening agent. 

Preservatives can be classified into two types compounds that release formaldehyde and compounds that do not release formaldehyde. Formalin, an aqueous solution of formaldehyde, is a commonly used preservative in shampoos and conditioners [3], Although formaldehyde has been known as a sensitizer, it is not a problem if used at 0.1 % or lower. The use of formaldehyde in baby shampoos is not recommended. Other preservatives that fall in the formaldehyde-releasing group are diazolidinyl urea, imidazolidinyl urea, and DMDM (dimethyloldimethyl) hydantoin. 

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