# US 11,298,298 B2 · Method for producing nonaqueous composition for external use on skin

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,298,298 B2
- Document ID: US11298298B2
- Status: Granted
- Kind: B2
- Application number: 16/753,396
- Filed: 2018-10-05
- Published: 2020-10-01
- Granted: 2022-04-12
- Earliest claimed: 2017-10-06
- Assignees: Chanel Parfums Beaute; Kyushu Univeristy, National University Corporation
- Applicants: Chanel Parfums Beaute; Kyushu University, National University Corporation
- Inventors: Masayoshi Miyamoto; Yoshihito Oda; Masahiro Goto
- Web page: https://patentgrep.com/patent/US11298298B2

## CPC

- A61K 8/0291: {Micelles}
- A61K 8/044: {Suspensions}
- A61K 8/31: Hydrocarbons
- A61K 8/37: Esters of carboxylic acids
- A61K 8/375: {the alcohol moiety containing more than one hydroxy group}
- A61K 8/44: Aminocarboxylic acids or derivatives thereof, e.g. aminocarboxylic acids containing sulfur; Salts; Esters or N-acylated derivatives thereof
- A61K 8/553: {Phospholipids, e.g. lecithin}
- A61K 8/604: {Alkylpolyglycosides; Derivatives thereof, e.g. esters}
- A61K 8/676: {Ascorbic acid, i.e. vitamin C}
- A61K 8/678: {Tocopherol, i.e. vitamin E}
- A61K 8/922: {of vegetable origin}
- A61Q 19/00: Preparations for care of the skin
- A61K 2800/262: Transparent; Translucent
- A61K 2800/31: Anhydrous
- A61K 2800/413: Nanosized, i.e. having sizes below 100 nm
- A61K 2800/82: Preparation or application process involves sonication or ultrasonication
- A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D)
- A61Q: SPECIFIC USE OF COSMETICS OR SIMILAR TOILETRY PREPARATIONS

## Abstract

A method for producing a nonaqueous composition for external use on the skin including a strongly hydrophilic amphiphilic solid active ingredient-surfactant complex dissolved or dispersed in an oil phase, the method including the steps of: dissolving a surfactant in an oil phase to obtain a surfactant solution; mixing the obtained surfactant solution with a strongly hydrophilic amphiphilic solid active ingredient to obtain a suspension; and allowing the obtained suspension to stand still to obtain a transparent composition. Unlike conventional methods for preparing S/O formulations, the strongly hydrophilic amphiphilic solid active ingredient can be solubilized in an oil phase without the process of emulsification and freeze drying.

## Claims

### Claim 1

A method for producing a nonaqueous composition for external use on the skin comprising a strongly hydrophilic amphiphilic solid active ingredient-surfactant complex dispersed in an oil phase, the strongly hydrophilic amphiphilic solid active ingredient being selected from the group consisting of palmitoyl-L-carnitine, hydroxycitryl palmitate, ascorbyl phosphate palmitate, (ascorbyl/tocopheryl) phosphate, cyclic lysophosphatidic acid, and salts thereof, the method being operated in the absence of water, and comprising the steps of:
(a) dissolving a surfactant in an oil phase to obtain a surfactant solution;
(b) mixing the surfactant solution obtained in the step (a) with a strongly hydrophilic amphiphilic solid active ingredient to obtain a suspension; and
(c) allowing the suspension obtained in the step (b) to stand still to obtain a transparent composition.

### Claim 2 (depends on 1)

The production method according to claim 1, wherein in the step (b), the mixing is performed using a high-speed stirrer or an ultrasonic stirrer.

### Claim 3 (depends on 1)

The production method according to claim 1, wherein in the nonaqueous composition for external use on the skin, the strongly hydrophilic amphiphilic solid active ingredient-surfactant complex is dispersed as a particle having a particle size of 2 nm to 100 nm in the oil phase.

### Claim 4 (depends on 1)

The production method according to claim 1, wherein the mass ratio of the surfactant to the strongly hydrophilic amphiphilic solid active ingredient is 2 to 50 times.

### Claim 5 (depends on 1)

The production method according to claim 1, wherein the surfactant is a nonionic surfactant.

### Claim 6 (depends on 1)

The production method according to claim 1, wherein the surfactant is one or more selected from the group consisting of glycerin fatty acid ester, polyglycerin fatty acid ester, polyoxyethylene glycerin fatty acid ester, sorbitan fatty acid ester, sucrose fatty acid ester, polyoxyethylene sorbitol fatty acid ester, polyoxyethylene castor oil and hardened castor oil.

### Claim 7 (depends on 1)

The production method according to claim 1, wherein the HLB value of the surfactant is 10 or less.