Shiseido Patent Details Use of UV-Activated Ingredients to Enhance Skin Care Benefits

Shiseido Company, Ltd., Tokyo, has been awarded two patents from the US Patent and Trademark Office that detail inventions that can harness UV light in a way that can benefit the skin.

The first patent details a cosmetic designed to convert ultraviolet light into visible light while simultaneously boosting the activity of certain skin care ingredients. Another recently awarded patent describes an O-I-W composition that converts UV light Into skin-activating visible light.

US Patent 12,551,418

In US Patent No. 12,551,418 B2 (Yusuke Okuyama, Kazuyuki Miyazawa, Nobuyoshi Koga, Tetsuya Kanemaru, Renaud Gillet, Bianca McCarthy), Shiseido details a cosmetic comprising a UV wavelength conversion substance and one or more drugs selected from the group consisting of a derivative of glycyrrhizic acid, a derivative of nicotinic acid, tranexamic acid, a derivative of salicylic acid, and a carboxylic acid represented by formula below, and salts thereof.

• wherein n represents an integer of 2 to 5;
• the (A) UV wavelength conversion substance comprises one or more selected from the group consisting of phycocyanin, vitamin B2, and a zinc oxide phosphor;
• the derivative of glycyrrhizic acid comprises dipotassium glycyrrhizinate;
• the derivative of the nicotinic acid comprises nicotinic acid amide;
• the derivative of the salicylic acid comprises potassium 4-methoxysalicylate; and
• the carboxylic acid represented by the formula (I) comprises 1-piperidine propionic acid.

According to the patent, the glycyrrhizic acid, nicotinic acid derivatives, tranexamic acid, salicylic acid derivatives and related carboxylic acids work alongside the wavelength-converting materials to promote cell activation in the skin when exposed to UV light.

The key mechanism involves materials that absorb ultraviolet radiation and re-emit it as longer-wavelength visible light (fluorescence). The inventors propose that this converted light can help stimulate cellular activity, potentially supporting processes such as skin metabolism, collagen production and barrier function.

The UV wavelength conversion components can include inorganic phosphors, such as zinc oxide phosphor or magnesium titanate phosphor, as well as organic fluorescent compounds.

The technology can be incorporated into a range of topical formats, including lotions, creams and emulsions. According to the inventors, the formulations generate measurable fluorescence when exposed to UV radiation and may increase cellular activity in skin cells such as fibroblasts and keratinocytes.

US Patent 12,551,424

The second patent awarded to Shisiedo (US 12,551,424 B2), details an O-I-W composition that converts UV light Into skin-activating visible light. The oil-in-water type emulsified composition that contains UV wavelength conversion substance; a water-soluble alkyl-substituted polysaccharide derivative; a dispersant; and one or more surfactants selected from the group consisting of an anionic surfactant, a cationic surfactant, an amphoteric surfactant and a nonionic surfactant.

The UV wavelength conversion substance comprises one or more selected from the group consisting of phycocyanin, a zinc oxide phosphor, and a magnesium titanate phosphor.

The water-soluble alkyl-substituted polysaccharide derivative comprises a stearoxyhydroxypropyl methylcellulose.

The dispersant comprises one or more selected from the group consisting of PEG-10 dimethicone, bis-butyldimethicone polyglyceryl-3, PEG-9 polydimethylsiloxyethyl dimethicone, lauryl PEG-9 polydimethylsiloxyethyl dimethicone, cetyl PEG/PPG-10/1dimethicone, isostearic acid and carboxydecyl trisiloxane.

The work in US 12,551,424 B2 is credited to Ryoya Ito, Kouichi Nagai, Shiho Iwami, Kazuyuki Miyazawa, Tetsuya Kanemaru, Renaud Gillet and Bianca McCarthy.