Phytosphingosine for Skin Differentiation and Other Topics: Literature Findings

By: Charles Fox, Independent Consultant

Posted: December 1, 2009, from the December 2009 issue of Cosmetics & Toiletries.

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Cationic polymer hair coloring: Boston Cosmetics LLC disclosed pigment-functionalized, cationic polymer compositions for hair coloring.⁴ A plurality of treatment formulations applied one after the other was used to improve the characteristics of hair coloring. Additional formulations or treatments, such as sealing compositions and final coating formulations, were then used to impart durability. Other formulations/compositions were discussed as well, including the processes for using such compositions.

Furthering the compositions, kits were assembled where the various compositions were compartmentalized for storage until the time of application. Thus, a dispersion was prepared comprising 3.75 g carbon black and 250 mg of a 50% aqueous solution of poly(ethyleneimine) in 67.5 mL water. Blonde hair was dyed black with the 50% diluted carbon black slurry and coated with maleic anhydride polymer. The black color did not rinse out with washing and was resistant to removal with mild abrasion.

Identifying actives for keratin fiber modification: L’Oréal has patented a method to select actives for modifying the shape of hair and the cosmetic use of such actives; no specific active was identified in the research.⁵ Steps to modify the shape of keratin fibers involve: culturing mammalian cells; adding the test substance to the culture; assaying the amount of glycosaminoglycan (GAG) in the mammalian cells or in the cell culture medium after incubation; comparing the amount of GAG measured with a control culture obtained under the same conditions but in the absence of the test substance; and selecting the substances for which the amount of GAG is modified by a factor of ≥ 0.5 relative to the control. An example hair straightening composition is shown in Formula 1.

Permanent hair waving with metal salts and sericin hydrolyzates: Seiren Co., Ltd. has disclosed hair treatment agents containing monovalent or divalent metal salts and sericin hydrolyzates and their use between reduction and oxidation processes.⁶ The title agents optionally contained keratin hydrolyzates to impart elasticity, shape-retaining properties, volume and smoothness to hair damaged by brushing, drying, bleaching, perming, etc.

Thus, a hair bundle damaged by repeated bleaching was wound around a rod and treated with the first agent containing a reducing agent at 45°C for 15 min. The bundle then was rinsed and treated with an aqueous solution of sericin hydrolyzates, magnesium chloride and citric acid for 10 min. Again, the hair bundle was rinsed and treated with a second agent containing an oxidizing agent at 45°C for 10 min. The bundle was rinsed and the rod removed. The hair bundle was dried at RT for 24 h and showed long-lasting curl retention, elasticity and a smooth texture.