Alkyl ether sulfates , shampoos

Shampoos based on lauryl sulfates can range from 6—17% of the active surfactant. However, though they are effective cleansers, the alkyl sulfates tend to be defatting. In an effort to make these shampoos more mild, many shampoos are now based on blends of amphoterics and alkyl sulfates or the less irritating alkyl ether sulfates. 

These higher foaming properties are very useful for such cosmetic formulations as shampoos, showerbaths, and so on. This is the same with the forming of fine bubbles and the improving of foam stability of other surfactants such as, for example, alkyl ether sulfates due to the combination with ether carboxylates [57,67-69] (Table 9). 

Although by 1957 [9] the use of ether carboxylates also in combination with other surfactants such as alkyl ether sulfates for shampoos had been described,... 

In combination with alkyl ether sulfates, a synergistic decrease of the irritation level of the ether sulfates and an improvement of the foam stabilization has been described [57,67,78]. A good compromise between mildness and foam properties could be achieved with lauryl ether carboxylic acid sodium salt with 10 mol EO [57,67]. In several articles examples of the use of alkyl ether carboxylates as cosurfactant in mild shampoos as well as bath and shower products have been described [57,69,79]. 

All of the aspects and applications described in papers can be traced back to the patent literature [73]. The special or synergistic effect of ether carboxylates in combination with other surfactants is very often the basis, like combinations with alkyl ether sulfates or alkyl sulfates, for shampoos, foambaths, showerbaths, and liquid soaps [9,70,81-85], and the same for amidether carboxylates [71]. 

Alkyl Ether Sulfates (AES) R=Cio C14 m=l-4 Liquid bath soaps, hair shampoos, and mechanical dishwashing agents. Ingredient in industrial cleaning agents - Effluents of seven representative STPs Cl2-15 AES 3 and 12 pg L 1 [15] Readily biodegradable in WWTPs under both aerobic and anaerobic conditions [18,29]... 

Cosmetic Rinse off Preparations. In certain cosmetic products, tor example hair shampoos, it is not possible to use complexing agents because of the irritation of mucous membranes. Here a low sensitivity of surfactants to water hardness is a precondition for their application. Foam formation is generally considered to be a measure of shampoo quality (Table V). With increase in water hardness the foam volume of alkyl sulfates decreases very much, whereas with the corresponding alkyl ether sulfates this decrease is relatively small. For cosmetic applications, the good skin compatibility and low irritation to mucous membranes of alkyl ether sulfates is of high importance (37). 

Alkyl Ether Sulfates. These surfactants are also found in shampoo applications. They are prepared similady to alkyl sulfates except that the fatty alcohol is... 

As mentioned in Section II.A.l(a), the presence of ethylene oxide moieties in alkyl ether sulfates reduces surfactant irritation. Polysorbate 20 and PEG-80, which have 20 and 80 moles of ethylene oxides, respectively, are often incorporated into baby shampoos as anti-irritants. Magnesium salts of these surfactants are also milder than the sodium salts. Table 10.8 shows an example of the formulation of a mild baby shampoo from U.S. Patent 3,928,251. More developments in mild and nonirritating shampoo formulas are listed in Table 10.9. 

Other soils have not been studied so extensively however, Robbins et al. [29] have shown that Cn alkyl sulfates or alkyl ether sulfates, the traditional shampoo surfactants, do not remove cationic surfactants from hair effectively under certain conditions. However, shorter chain-length anionics such as deceth-2 sulfate is more effective for removing cationics. In addition, alkyl ether sulfates are more effective for removing fatty acid soils in the presence of water hardness than alkyl sulfates [29]. 

Alkyl ether sulfates (AES), which are the sulfuric add monoesters of alfcoxylated alcohols, are the most widely used surfactants in detergent personal care products. They are mainly encountered in liquid formulations such as shower gels, bath foams, and shampoos. Their chemical formula is as follows ... 

A characteristic example in the field of cosmetics is the separation and determination of anionic surfactants in shampoos. The only required sample preparation step is the dilution of the product to be analyzed in de-ionized water and subsequent membrane filtration (0.45 pm) prior to injection. Figure 9-129 illustrates the gradient elution of anionic surfactants in a commercial shampoo with simultaneous non-suppressed conductivity and UV detection. While the peak pattern in the UV trace indicates the presence of alkylbenzene sulfonate (ABS) (see also Fig. 6-42 in Section 6.5), the characteristic peak profile for alkyl-ether sulfates (see Fig. 6-41 in Section 6.5) is evident in the conductivity trace after visual subtraction of the ABS signal. Therefore, ion chromatography provides a way to unequivocally identify surfactant raw materials in finished cosmetic products without time-consuming sample preparation. 

Mild branched chain alkyl ether sulfates for use in shampoo and bath products. These products have excellent wetting and foaming properties. Their mildness is ideal for use in t>aby products. 

Alkyl Ether Sulfates These surfactants are also found in shampoo applications. They are prepared similarly to alkyl sulfates except that the fatty alcohol is first subjected to ethoxylation ethoxylation may range from 2 to 3 moles per mole of fatty alcohol. Lauryl alcohol is the typical fatty alcohol reacted. Because of high water solubility, alkyl ether sulfates have low cloud points, making them suited for clear shampoo formulations (5). Viscosities based on the ether sulfates can be easily controlled through addition of inorganic salts such as sodium chloride. 

Chem. Descrip. Triethanolamine polyorryethylene alkyl ether sulfate Uses Foaming agent, detergent for cosmetics, pharmaceuticals, high foaming/low skin irritation shampoos Properties Lt. yel. liq. =40% act. 

Uses Surfactant, foam builder, and cleansing agent in cosmetics, personal care, shampoos coupling agent vise, builder Sodium CIO-14 alkyl benzene sulfonate Synonyms Benzenesulfonic acid, C10-C14-alkyl-, sodium salts Uses Emulsifier In cosmetics Sodium C12-15 alkyl ether sulfate Uses Cosmetics dishwashing Ingred. 

Alkyl ether sulfates, also called alcohol ethoxysulfates, are prepared by addition of one to four oxyethylene groups to an alcohol which is then sulfated. Oxyethylation enhances water solubility and foaming over the analogous alcohol sulfate, giving a product useful in shampoos and in liquid and powdered detergents. The raw material for these products can be either natural fatty alcohols or primary or secondary synthetic alcohols, usually of C12-C18 chain length. The analogous alkylphenol ether sulfates are found in industrial applications. Ether sulfates are not as sensitive to water hardness as are other anionic surfactants. 

The most common ingredient in shampoos is also the most common detergent in use in other products a class of surfactants known as straight-chain alkyl benzene sulfonates. Examples are ammonium lauryl sulfate, its sodium relative, and the slightly larger but related molecule ammonium lauryl ether sulfate (sometimes abbreviated as ammonium laureth sulfate). 

The applications of alcohol sulfates in consumer products depend on the alkyl chain and in some cases on the cation. Alcohol sulfates with alkyl chains 8 C1() are seldom used in consumer products except occasionally as hydrotropes in liquid detergent formulations. However, alcohol sulfates in the range C10-C18 are used in many commonly used formulations although other surfactants are generally added to enhance their properties. In some of these applications, particularly in shampoos, they compete with alcohol ether sulfates of the same alkyl chain distribution. The pattern of use of alcohol sulfates or alcohol ether sulfates in formulations varies with consumer personal care and laundry washing preferences in different cultural areas of the world. 

Until the 1950s ether carboxylates were almost in very limited amounts in the textile industry. It was only in 1957 [9] that the first ethercarobxylates were mentioned, in combination with other surfactants such as alkyl sulfates and ether sulfates, for use in shampoos. In spite of the special properties of ether carboxylates, their use was low in the industry as well as in cosmetics at that time. This was also due to the fact that at that time properties such as toxicity, biodegradability, and mildness to the skin did not have the high priority they do now. 

Phosphoric acid esters of alcohols or ethoxylated alcohols are recommended as surfactants which are mild to the skin. Thus they are successfully used in cosmetics such as shampoos and lotions. In analogy to alkyl sulfates and alkyl ether... 

These alkyl dimethyl amine oxides are used as foam stabilizers primarily in light-duty liquids and shampoos where the major active ingredient is either an alcohol ether sulfate or an alcohol sulfate. The alkyl group is usually C19 to C.. which gives the best overall foam stability (3). 12 14... 

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