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Formulating with Naturals—Hair Care
By: Art Georgalas, Georgalas Endeavors LLC
Posted: April 5, 2011, from the April 2011 issue of Cosmetics & Toiletries.
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Hair conditioners: Hair conditioners deliver the eponymous benefit of hair conditioning, but what exactly does this mean? Looking at how one actually tests hair conditioning—i.e., via tress testing and half-head salon testing—can provide formulators with answers. In answer to these tests, key conditioner benefits would therefore include reducing the force necessary to comb through wet and dry hair fibers as well as reducing the surface charge on hair fibers, in this case excess negative energy, to reduce electrostatic repulsion and the macroscopic appearance of fly-away. And what better way to impart these effects than applying a species that has both a positive charge and a long molecular chain of low intermolecular attractive forces, such as hydrocarbon or silicone polymers. In the conditioner arena, these would be cationic surfactants, exemplified by quaternary ammonium salts or quats, but these are severely restricted by most private natural certifiers.
However, formulators can look to amino acid derivatives as a way out of this dilemma. Two examples are PCA ethyl cocoyl arginate and brassicyl isoleucinate esylate, which can provide hair conditioning. Like their parent compounds, i.e. proteins and amino acids, they are naturally amphoteric. Thus, the pH of the system governs their functionality, as dictated by their isoionic points. Although not promoted as heavily as in the past, the acyl derivatives of amino acids and proteins may eventually be the shining light of naturals for hair treatments—both for cleansing and conditioning. Combinations of vegetable oils and jojoba oil and other emollients also find their way into hair conditioners, as well as lecithin, usually of soy origin, all of which are available in NOP organic versions. These materials have some substantivity to the hair cuticle, virgin hair more than damaged, and can serve as a friction-reducing film on the hair shaft. These ingredients are also seen in conditioning shampoos and body washes, although most of their conditioning effects are washed down the drain.
It is important to remember that when looking at natural derivatives, some simple naturals can be derived via synthetic routes. Glycine, the smallest amino acid, for example, is abundant in nature but it is difficult to distinguish the natural from the synthetic; having no substituent on the carbon between the carboxyl and amine groups, it does not have positive and negative optical isomers as all the other proteogenic amino acids do. One cannot tell the feedstock source simply because it is not chiral. The same is also true for glycerol-based derivatives; there are both synthetic and naturally derived versions from vegetable oils and fats, as well as natural biological building blocks of animal origin, so formulators may want to ask their suppliers to certify the source.
Further, the same can also be an issue also with preservatives and fragrances. Some nature-identical preservatives are allowed under certain certification systems, e.g. NaTrue, but are only allowed under NSF/ANSI 305 if they are derived from non-petrochemcial feedstocks. Fragrance also can have natural roots, and many flavor and fragrance houses can provide natural fragrances. Combinations of related essential oils, many available as NOP Organic, can form pleasant compositions but professionally developed natural fragrances are better suited to most products. Aromatic extracts of fruits and flowers are also available if that is the chosen marketing direction.
There are, however, severe limitations in relation to color since many colors extracted from plants are not approved for cosmetic use, even if they are approved for food and drug use. The soluble dyes that can be used include caramel, annatto, beta-carotene and carmine from the Mexican cochineal insect.6 Formulators are not likely to use inorganic pigments such as titanium dioxide, iron oxides or chrome oxides, which go into color cosmetics, in hair care. There is also the unique copper chelate disodium EDTA-copper, which is only approved for use as a shampoo colorant but unfortunately it is not natural.