Style retention

U.S. 5334376 (1994) Robbins et al. (Colgate-Palmolive) Particulate barium sulfate combined with one or more coreactants from the following groups silicone free of amino group, long-chain fatty alcohol, long-chain fatty acid amide Improved body, manageability, and style retention to hair... 

Recently, Diaz et al. [101] have demonstrated that exposure of water-set hair tresses to a lower humidity can also produce a loss of set. In addition, Robbins and Reich [102] have demonstrated this same phenomenon with single hair hbers. Thus, we conclude that exposure of water-set hair to changes in humidity results in the flow of additional moisture either into or out of hair. This moisture transfer, therefore, breaks hydrogen bonds critical to water-set stability, resulting in a decrease in style retention. 

Hairsprays, setting lotions, and mousses are related in the sense that each of these products applies a resinous material to the hair and helps to maintain style retention by enhancing interfiber interactions. If the hair is not combed after the resin has set (after the solvent evaporates), rigid contact sites of resin are formed between fibers, analogous to strip welding (Figure... 

Surfactants and oils are also present in most mousse formulations. Surfactants function to lower the surface tension to help spread the polymer film over the hair surface and to support the foam character of the product. Mousses are added to wet hair. They are combed through without rinsing, to distribute the product through the hair. The hair is then styled and dried. Mousses can improve wet hair manageability by lowering combing forces. They also enhance body and style retention. 

With these products, the hair is combed dry, after the solvent has evaporated. Therefore, they cannot provide a large number of rigid contacts as hairsprays do however, they do enhance interfiber attractive forces to provide increased body and improved style retention. 

Because the mode of application of these products is similar to the mousse and involves combing the product through wet hair prior to setting and drying and then recombing the hair after it has dried, these products do not function by forming rigid bonds exactly as hairsprays do. Nevertheless, these products do enhance interfiber forces to provide increased hair body and improved style retention. 

To develop and evaluate hairsprays, setting products, and mousses, a variety of methods have been developed. The methods described in this section have been developed primarily for hairspray formulation and evaluation. Style retention is without question the most important property of hair-sprays, and several approaches to evaluating hairspray holding power have been described in the literature [59-61]. One novel approach by Ganslaw and Koehler [62] involves measurement of the rate of untwisting of hair swatches treated with hair fixative solution. This parameter, which these authors call twist retention analysis, correlates with curl retention and is claimed to allow for more rapid evaluation of data. 

Cross-sectional shape, friction, density, and static charge are described as other important physical properties, and hair shine, combing ease, body, style retention, manageability, and hair conditioning are the primary important consumer assessments described in this chapter. A new section describing normal variation that exists in the cross-sectional shape of hair fibers and a few examples are given describing how these variations influence both the physical and the chemical behavior of the fibers. 

Robbins [121] has also developed a procedure for determining dry static friction at low load (in the milligram range) by modification of the incline plane fiber loop method of Howell and Mazur [124]. This procedure attempts to measure those intimate fiber-fiber interactions associated with hair body and style retention, by determining the angle of slip for a small hair loop sitting on two parallel hair fibers. Above a 1-mg load, the frictional coefficient decreases very slowly with increasing load. However, below a... 

Keeping hair in place (style retention during styling)... 

Style retention may be dehned as the ability of hair to stay in place after styling. It is time-dependent and includes curl retention, wave retention, and straightness retention. Style retention may be described in terms of single-hber properties, or it may be treated as an assembly property. It is most important to permanent waves and to hairsprays as well as to conditioner sets or wave sets and mousses. 

Table 8-30. How single-fiber properties relate to style retention [1],...

A curvature increase can increase or decrease style retention (see text). 

The maximum fiber curvature consistent with the desired styling will produce the maximum number of entanglements, the maximum fiber-fiber interactions, and thus the maximum style retention. Generally, an increase in fiber curvature will increase style retention. However, if the desired style is considerably straighter than the natural curvature, then a decrease in fiber curvature will be necessary to improve style retention (hair straighteners or relaxers). The converse holds for styles that are curlier than the natural curvature of the hair. 

Both permanent waving and relaxing of hair improve style retention. Obviously, the type and size of rollers (curlers) in permanent waving are important in determining the final result, and they should be consistent with the curvature required for the desired hairstyle. Permanent waving also increases interfiber friction [122] and this property contributes to improve style retention. 

Bleaching increases interfiber friction [122,123], thus helping to improve style retention. Most creme rinse ingredients [123], in contrast to bleaches, provide a decrease in interfiber friction and thereby decrease style retention, except for most straight hairstyles. 

Conditioner sets, setting lotions, mousses, and hairsprays all increase the interfiber attractive forces that help to improve style retention. These effects are greater than that of the weight increase of these ingredients that would tend to decrease style retention. 

High-cleaning shampoos, when used on hair containing sebaceous sou, remove the surface oils and thereby reduce the cohesive bonding between fibers. These products thus provide for an improvement in style retention for dry look hairstyles. Certain conditioning shampoos provide a decrease in fiber friction and an increase in cohesive bonding and thereby provide for a limp look and a decrease in style retention for most styles. 

Existing tests to evaluate hair-combing ease, style retention, and flyaway hair or static charge may then be used to evaluate these different types of manageability. Furthermore, each type of manageability may be expressed in terms of a ratio of control/treatment values. 

The apparent bulk that hair assumes after grooming is an important aesthetic characteristic often referred to as body, which can be considered a property associated with Robbins term style retention. Tolgyesi and co-workers (67) proposed the following definition of this hair assembly property Body is a measure of a hair mass s resistance to and recovery from externally induced deformation. This definition correlates well with the descriptive components springiness, volume, and stiffness that Wedderbum and Prall have obtained by applying statistical techniques to word association (58). The structural strength and resiliency of the hair mass are influenced by a number of independent parameters. Tolgyesi has identified the five most important parameters as fiber density... 

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