02.24.23
US Patent No. 11,583,488 B2 (Lu Zhang, Peter Brendan Styczynski, Sudeep Chakravarty, Joseph Michael Zukowski, Chuiying Li, Mason); The Procter & Gamble Company, Cincinnati, OH, has patented a method of improving skin penetration of a vitamin B3 compound where skin health or appearance benefit is desired. It entails applying a low-pH skin care composition comprised of a first concentration of a vitamin B3 compound and a pH less than 5; and thereafter applying a second skin care composition that is comprised of a second concentration of the vitamin B3 compound. The second concentration is higher than the first concentration.