Amphoteric surfactants liquid soaps

Parris, N. (1978). Surfactant analysis by high performance liquid chromatography I. A rapid analysis for mixtures of amphoteric surfactants and soap. J. Am. Oil Chem. Soc. 55(9), 675-677. 

Of the four types of synthetic surfactants, anionic, cationic, amphoteric, and nonionic, the anionic surfactants provide maximum lather and hence are used as major components in liquid products. The active ingredients used in the major brands of liquid soaps are described by Dyer and Hassapis [6],... 

Cationic and nonionic surfactants are not very common for bar products. However, they can be used at very low levels for certain functional properties. Anionic and amphoteric surfactants are more cost-effective, and have balanced mildness with excellent lathering properties. Some of the nonionic surfactants such as sugar esters and amphoacetates have very good mildness and lathering properties, but are not cost-effective. These surfactants are suitable mainly for liquid products. In combination with fatty acid soaps, SCI, suUbsuccinate, AGES, AOS, and CMGS have been used as surfactants in syndet and combars. 

The amphoteric surfactants are relatively expensive products compared to anionic surfactants. Thus, it is not surprising that they are primarily being utilized at low concentrations in cosmetic formulations. A review of 438 shampoos of the U.S. market reveals that appreciable quantities, for example, >5% of alkylamido betaines and imidazolinium surfactants were found in only 8.7% and 13.5%, respectively, of the investigated shampoos. Alkyl betaines were found in a limited number of cases, whereas sulfo betaines were not found in this stndy [4,5]. Since these studies were made, the market has focused on mild products. The change in the U.S. market from bar to liquid soaps has increased the use of alkylamidopropyl betaines. 

Dimethylaminopropylamine is an aliphatic amine present in amphoteric surfactants such as liquid soaps and shampoos. It is present as an impurity responsible for allergy from cocamidopropylbetaine. It is structurally similar to diethylaminopropylamine. It is also used as a curing agent for epoxy resins and as an organic intermediate in chemical syntheses (ion exchangers, additives for flocculants, cosmetics and fuel additives, dyes and pesticides). 

ATR-FTIR is a useful analytical tool for multicomponent analysis that employs a mathematical data-treatment process. Also, Carolei and Gutz (2005) have used this technique combined with chemometrics, to determine three surfactants and water simultaneously in shampoo and in liquid soap without either sample dilution or pretreatment. The surfactants analysed were an amphoteric one (cocoamidopropyl betaine), two nonionic ones (coco diethanolamide in shampoo and alkylpolyglucoside in liquid soap), (minor components) and an anionic one (sodium lauryl ether sulfate). Overlapping bands and water absorption were resolved by two multivariate quantification methods classical least squares (CLS) and inverse least squares (ILS) (Massart et al., 1997, 1998). The wave numbers chosen for the calculation process were preferably those of maximum absorption of the minor components. This method can be applied during the production process but not in final product analysis because of interference caused by the fragrance added in the last step (Figure 7.1.2). 

These can be produced in the form of liquids, creams, gels, powders, granules (beads). Their main function is to produce maximum foam into running water. The basic surfactants used in bubble bath formulations eire anionic, nonionic or amphoteric together with some foam stabilizers, fragrants and suitable solubilizers. These formulations should be compatible with soap cUid they may contain other ingredients for enhancing skin care properties. 

Uses Emulsifer, stabilizer, pearlizer, opacifier for hand dishwashing detergents, rinses, cosmetics, liquid hand soaps, body cleaners, and shampoos Features Compat. with cationic, amphoteric, anionic and nonionio surfactants Properties Wh. flake HLB 1 acid no. 6 max. sapon. no 190-200 100% solids Canocol EGDS-35 [Centro China]... 

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