Boosting SPF with Copolymers and Other Topics: Literature Findings

By: Charles Fox, Independent Consultant

Posted: April 30, 2010, from the May 2010 issue of Cosmetics & Toiletries.

This month’s survey of recent patent and research literature describes moneymaking ideas for personal care development, including an anti-inflammatory to soothe the skin post raw material irritation, lactulose for hair styling, reducing the damage caused by perms, boosting SPF with copolymers and the treatment of skin with heated lotion, among others.

Skin and Skin Care
Light activation of cytochrome C oxidase: L’Oréal has disclosed the activation of a cytochrome C oxidase substrate with light radiation to improve the appearance of skin and/or hair.¹ The invention comprises the simultaneous and/or sequential administration of: at least one cytochrome C oxidase substrate, at least one agent to increase the expression of said substrate, and at least one light radiation source with a predominant wavelength ranging 550–1,000 nm, preferably 640–680 nm, to activate the cytochrome C oxidase. A radiation dose ranging 0.01– 200 J/cm², specifically 5–30 J/cm², was applied in the described method. The invention also relates to a kit including all three components. An example of a skin improvement cream is shown in Formula 1.

Refreshing DHA self-tanner: Coty Prestige Lancaster Group GmbH has patented a self tanner comprised of 1.0–3.0% w/w dihydroxyacetone (DHA), 8.0–35 % w/w water, 5.0–30 % w/w wax and 3.0–35% w/w oil, 1.0–7.0% w/w pigments and additional cosmetic agents and excipients.² The compositions are free from emulsifiers, and the ratio of water to oil is 0.8–1:1.5–3. This storage-stable composition is said to produce instantaneous, even and continuous tanning with a feeling of freshness. An example is shown in Formula 2.

Anti-inflammatory to soothe irritation: Symrise GmbH and Co. has disclosed the use of 3-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)-1-propanone in cosmetic and pharmaceutical preparations as an anti-inflammatory agent to soothe the irritation caused by other cosmetic ingredients.³ The described compositions contain additional anti-inflammatory agents and sunscreens with SPF > 2. P-hydroxyacetophenone was reacted with vanillin to prepare 3-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)-2-propene-1-one, followed by the catalytic hydrogenation of the product to obtain the title compound. An example of a skin lightening cream with the anti-inflammatory agent is shown in Formula 3.

Hair and Hair Care
Cationic surfactant hair conditioners: L’Oréal has patented the use of two separate cationic surfactants as conditioners in hair care compositions, as well as a process for treating hair with the compounds.⁴ The first composition utilizes cationic quaternary ammonium esters derived from 2-[2-(diethylamino)ethoxy] ethanol as the conditioning agent. 2-[2-(Diethylamino)ethoxy]ethyl decanoate was reacted with diethylsulfate to obtain 2-[2-(decanoyoxy)ethoxy]-N,N,N-triethylethanaminium chloride. A hair preparation composed of 15% inulin, 2% pectin, 1% 2-[2-(decanoyoxy)ethoxy]-N,N,N-triethylethanaminium chloride and balance of water is provided.