Shampoo lather

Robbins suggested that the rate of lather generation and the feel of the foam are two other important elements of shampoo lather. Methods for evaluating these two elements have not yet been well developed [3],... 

Hart and Neu have provided a useful beginning to a better understanding of shampoo lather, of lather testing, and of the effects of additives on shampoo lather. However, Hart s lather drainage rates are only one of the important components of shampoo lather that is relevant to the consumer s perception. Lather feel and the rate of lather generation are two other important components of shampoo lather as of this writing, methods for these important lather components have not been described in the scientific literature. 

In some cases, foam stability and resistance to soil addition are important properties. Shampoo lather must be resistant to sebum, hard water, and the addition of special ingredients like a refatener or a conditioner. Foam bath must be resistant to soap and body soil. Hand dishwashing products should demonstrate good foam mileage even in the presence of a heavy soil load (greasy or starchy soils). 

Hlkanolamides. The fatty acid alkanolamides are used widely ia shampoo formulations as viscosity and lather builders. They are formed by the condensation of a fatty acid with a primary or secondary alkanolamine. The early amides were compositions of 2 1 alkanolamine to fatty acid. Available technology allows the formation of amides with a 1 1 ratio of these additives. These amides are classified as superamide types. The typical amide used ia shampoo preparations usually contains the mono- or diethanolamine adduct, eg, lauric diethanolamide [120-40-1] (see Amides, fatty acid). 

To sell well, the shampoo must look good, must feel thick or creamy in the hands, and must produce a nice-feeling lather. It must smell good, and it must not be too expensive. Other selling points might be the currently popular herbal extracts, or amino acids from exotic protein sources such as silk or the milk of pygmy goats. 

Not all bars that lather contain just soap. Many feature the same detergents that you find in shampoo as well. 

Sodium isethionate is an amphoteric detergent used in detergent bar soaps. It makes a dense lather in addition to the lather made by the soap. It is nondrying and mild on the skin. It works equally well in soft or hard water. It is also an antistatic agent in shampoos. 

Since we want the texture of products like shaving cream to stay stable, and since shampoo advertisers like to pretend that unnecessary extra lather is an important selling point, foam stabilizers are helpful in preventing foams from breaking down. 

Head lice, crab lice Topical Apply about 30 ml of shampoo to dry hair and massage into hair for 4 min. Add small amounts of water to hair until lather forms, then rinse hair thoroughly and comb with a fine tooth comb to remove nits. Maximum 60 ml of shampoo. 

Lindane (Kwell, etc) is available as a shampoo or lotion. For pediculosis capitis or pubis, one application of 30 mL of shampoo is worked into a lather and left on the scalp or genital area for 5 minutes and then rinsed off. No additional application is indicated unless living lice are present 1 week after treatment. Then reapplication may be required. Recent concerns about the toxicity of lindane have altered treatment guidelines for its use in scabies the current recommendation calls for a single application to the entire body from the neck down, left on for 8-12 hours, and then washed off. Patients should be retreated only if active mites can be demonstrated, and never within 1 week of initial treatment. 

Dissolve sodium lauryl sulfate, a surfactant with a detergent s amphiphilic properties, in water. (This compound creates lather in car washes, shampoos, bubble baths, etc.). We use it here because it does not have an odor of its own. Use 750-ml powder in 15 1 of warm water (or prepare a smaller volume). 

Using a no-tears baby shampoo (dilute the solution if irritation occurs) form lather on the washcloth. 

A (select settings) B1 (position customer) 82 (apply water) Cl (spray shampoo) C2 massage lather) D1 (spray water) D2 (massage 8 rinse) D3 (drain) E (update status)... 

To use shampoo, the hair should be thoroughly wetted and sufficient shampoo applied to work up a rich lather and cover the entire scalp and neck area. The shampoo is left on for at least 5 minutes, rinsed off and the process repeated. The hair is then wet-combed. 

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. 

The main function of the primary surfactants in a shampoo is to provide a cleaning benefit. Primary surfactants are also necessary for adequate foam and viscosity control. As stated above, levels of surfactant between 8 and 20% are generally employed in shampoos. These levels are chosen primarily to provide acceptable lather and viscosity, since many common soils, e.g., sebum, are adequately cleaned at lower surfactant concentrations. 

Fatty alkanolamides are another class of commonly employed nonionic surfactants. These are used in shampoos to enhance lather and viscosity. The most frequently used alkanolamides are cocoamide DEA (diethanolamide) and... 

Amine oxides are also employed to improve foam characteristics and stabilize lather, especially at moderately acidic pH values. CAP (cocamidopropyl) amine oxide is one of the most commonly used amine oxides. These materials act as nonionics at the near-neutral pH encountered in shampoos but are easily protonated at acidic pH. As a result, they sometimes behave as cationics and act as conditioning and antistatic agents as well in a properly formulated system [13,19],... 

Betaines act as foam modifiers, changing the loose and lacy foams normally generated by lauryl and laureth sulfates to thick and creamy lathers. They also help to thicken shampoo formulations and lower eye and skin irritation [21,22],... 

Solubilization is particularly important for hair cleansing because under normal shampooing conditions a significant concentration of micelles is expected to be present. Thus, final surfactant concentration in the lather during shampooing has been estimated to be 1 to 2%, a value that is 5 to 10 times the CMC of SLS [1], This is an important value in view of reports that, for several surfactants, maximum detergency in cleaning of various fats and oils occurs at 6 to 10 times the CMC [130,131],... 

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