Alcohols sulphate formulation

Alcohol ether sulphates (AES) and alcohol sulphates (AS) are shown combined in Figure 1.9 since it is rarely possible to differentiate when products are formulated to contain both materials. Cost competition and producer preferences show their effect on the often erratic consumption of the surfactants over time. 

These are the major anionic surfactants used in all ranges of household detergents formulation, but especially in heavy duty laundry products, sometimes in combination with nonionics, alcohol sulphates of the tallow range and soaps. 

The broad cut (Ciq-Cis) alcohol sulphates represent a compromise of cost/performance in terms of detergency, solubility and foaming properties. This product can partially or totally substitute other anionics in liquid and powder detergent formulations with the advantages of good biodegradability and low "defatting" action which is important for human tissue and delicate natural or synthetic fibres. 

Formulations containing an absorption promoting substance, such as propylene glycol or sodium lauryl sulphate, may increase the permeability of the stratum comeum to water-soluble drugs. Propylene glycol is a commonly used vehicle in topical corticosteroid preparations for veterinary use. Various aprotic solvents, which include dimethylacetamide, dimethylformamide, dimethylsulphoxide, tetrahydrofurfuryl alcohol, and 2-pyrrolidone, serve as penetration enhancers of polar drugs (Barry, 1983). Dimethylsulphoxide... 

Products containing combinations of constituents with local anaesthetic and analgesic effects, such as lidocaine, choline salicylate and phenol, counterirritants such as ammonia solution and menthol, and astringents such as zinc sulphate and tannic acid, are marketed to reduce discomfort and promote faster healing of sores while the infection takes its course. Some are formulated with alcoholic bases, which may have a drying effect on sores and speed up healing. The bland cream bases of some products may have a soothing effect. 

The development of cosmetic microemulsion cleansers with alkyl polyglycosides (APG) was described by Forster et al. [4]. This class of non-ionic surfactants has excellent environmental and skin compatibility. Cosmetic cleanser multicomponent systems are required to have good foaming and cleansing performance. Figure 8.3 shows a pseudo-ternary phase diagram of a five-component formulation. It consists of water, the oil dioctyl cyclohexane (DOCH), the non-ionic surfactant C12/14-APG, the anionic surfactant fatty alcohol ether sulphate (FAES) and the co-surfactant sorbitan monolaurate (SML). The phase diagram... 

A microemulsion is water/hydrocarbon dispersion stabilized by an ionic surfactant such as a soap, alkyl sulphate or sul-phonate and most often also contains a cosurfactant in the form of a medium chain length alcohol (pentanol). Of these four components water, surfactant and cosurfactant are called the structure forming elements since they form colloidal association structures similar to the microemulsions with no hydrocarbon present. The formulation and preparation of microemulsions is greatly enhanced by a knowledge of these composition dependent structures, hence an introductory description of them will be given. 

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