Personal care products stability

Although most colloidal dispersions are not thermodynamically stable, a consequence of the small size and large surface area in colloids, and of the presence of an interfacial film on droplets, bubbles or particles, is that dispersions of these species, having reasonable kinetic stability, can be made. That is, suspended droplets or particles may not aggregate quickly nor settle or float out rapidly and droplets in an emulsion or bubbles in a foam may not coalesce quickly. Many food and personal care product emulsions and suspensions, for example, are formulated to remain stable for months to years. It is crucial that stability be understood in terms of a clearly defined process, and one must consider the degree of change and the time-scale in the definition of stability. 

No systematic studies of the use of silicone surfactants as emulsifiers have yet been published. Silicone polyoxyalkylene copolymers with relatively high molecular weight and a high proportion of silicone are effective water-in-silicone oil emulsifiers and a recent study of these copolymers suggests that they stabilize emulsions by a solid-particle mechanism [68]. This type of silicone surfactant has been used to prepare transparent water-in-oil emulsions (often with an active ingredient in the internal phase) for use as deodorants or antiperspirants as well as cosmetics and other personal care products. Their use as drug delivery vehicles has also been claimed. These copolymers can also be used to prepare multiple emulsions not requiring a two-pot process. 

Acetol Acetylated lanolin alcohol Acetulan . Acetylated lanolin alcohol binder for pressed powders emollient, plasticizer, cosolvent, NV and sebum solvent for personal care products lubricant for clay, talc, and starch stabilizer for lanolin solubilizer in Aerosols penetrant and spreading agent. Pale yellow oil d 0.867 miscible with mineral oil, castor oil, vegetable oil, i-PrOH, EtOH, isopropyl palmitate, butyl stearate. Amerchol. 

The range of personal care products is rather wide, such as shampoos, foam baths, shaving products, creams, tooth pastes. An almost complete review of the use of surfactants for cosmetic and personal care purposes was given in [80], We see it necessary to focus on two aspects of the effect of surfactants on the stability of dispersed systems under different application conditions. 

Cosmetic manufacturing needs suppressing the volatilization of perfumes, room fresheners and detergents. The major benefits of CDs are stabilizing and controlling the release of the cosmetic and personal care products from the inclusion complexes. CDs can also generate an improvement upon conversion of a liquid component to a solid form. Thus, CDs are widely applied in the main fields of skin creams, toothpaste, tissues, imderarm shields, liquid and solid fabric softeners and paper towels. 

There are many industrial processes in which the formation of low internal phase or concentrated emulsions needs to be controlled in terms of formation, stability, destruction or prevention. Examples range from asphalt emulsions to personal care products, and to food products. Success in emulsion control requires achieving the right physical chemistry and also the right fluid mechanics. In addition to HLB (see Section 7.2.1), both the nature of the emulsification method and the oil-water ratio are critical in determining the produced emulsion type. It appears that the emulsification technique (applied shear and oil-water ratio) used can be of greater importance in determining the final emulsion type than the HLB values of the surfactants themselves. 

Sucrose esters of fatty acids having 12 or more carbon atoms display surface active properties. Most of them are odourless and tasteless (or slightly bitter) allowing them to find applications both in food and personal care products [17]. Sucroesters were approved and freely permitted in Japan for use as food additives in 1959 for both their emulsifying ability and their heat stability. In addition, they are well known to protect food proteins from thermal denaturation and inhibit the growth of Escherichia coli and other bacteria. 

Amphoterics are excellent foamers and foam stabilizers under a variety of conditions. Their foamability is essentially insensitive to water hardness. Capitalizing on these properties, amphoterics were among the many specialty surfactants commercialized after World War II [2]. Since then, these surfactants have been used in personal care products because of their unsurpassed mildness and low eye-sting properties. Today, most mild skin cleansers and shampoos contain an amphoteric surfactant as a major component. 

PVP was one of the first successful hair fixative resins (Section III) (44). However, in this application today, it is more frequently present as a copolymer. PVP homopolymer is often employed in solution-based personal care products as a viscosifying and emulsion-stabilizing polymer. Simple emulsions that employ PVP benefit from its stabilizing effects. It has been suggested that, although solutions of PVP display yield stress, the magnitude of this effect is not always sufficient to stabilize emulsions, especially complex multiple ones (45). 

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