Natural Hair Dyes, Self-tanning Solutions and Other Topics: Literature Findings

By: Charles Fox, Independent Consultant

Posted: October 30, 2009, from the November 2009 issue of Cosmetics & Toiletries.

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Iridescent, continuous-phase soap bars: Unilever PLC, Unilever N.V. and Hindustan Unilever Ltd. have developed iridescent, continuous-phase soap bars with an ordered, layered microstructure comprising soap, water and ethoxylated alcohols.⁵ The phenomena of continuous-phase iridescence in a soap bar is characterized by a blue hue where the intensity depends upon the viewing angle and the background color used by the viewer for its observation. In a preferred embodiment, the iridescent soap bar is prepared with equipment capable of intensive mass shearing and generating high compression and extensional forces on the processed soap mass.

Moisturizing with cross-linked polyglutamate: Toyobo Co., Ltd. has researched skin moisturizing cosmetics containing water, alcohol and cross-linked poly-gamma-L-glutamic acid as a skin moisturizer. The cross-linked poly-gamma-L-glutamic acid had a gelation degree of 50–100% at 0.001– 5% w/w as a skin moisturizer.⁶ For example, sodium polyglutamate was obtained from a culture medium of Natrialba aegyptiaca and cross-linked using gamma-ray irradiation. The obtained cross-linked polyglutamate was mixed at 0.01% w/w with 10% w/w ethanol, 0.5% w/w fragrance and water to 100% w/w.

Hair and Hair Care
Natural hair dyes: Henkel AG & Co. KGaA discloses hair dyes containing natural dyes and 1,3-dihydroxyacetone.⁷ The natural dyes incorporated into this composition include derivatives of: diarylmethane, naphthoquinone, anthraquinone, flavonoids, betalain, gallotannin and indigoids. The dyes are intense and resilient. An example is shown in Formula 2.

Travoprost for hair loss: Galderma Research & Development utilizes travoprost to treat hair loss.⁸ The invention described indicates the topical application of a travoprost composition to stimulate or induce the growth and/or reduce the loss and/or increase the diameter and/or reduce the heterogeneousness of the diameter of the human hair stem with at least 24 hr between applications. The efficacy of a daily topical application of 0.01% w/w travoprost was shown to stimulate hair growth in guinea pigs.

Hair relaxer kit: Nippon Fine Chemical Co. discloses a relaxer kit and method for processing smoother hair.⁹ The kit was shown to improve hair smoothness and elasticity in a shorter time. The first of the two products in the kit contained a trialkoxyalkylsilane, an inorganic acid, an organic acid, a lower alcohol and polyoxyalkylene-modified silicone. The trialkoxyalkylsilane is represented by a general formula R1Si(OR2)3, where R1 and R2 = C1-4 alkyl. The second product in the kit contained a basic substance and a lower alcohol. The method for producing smoother hair included mixing the first and second products and applying them to the hair with heat to form a coated membrane on the hair. An example is shown in Formula 3.