09.08.22
US Patent No. 11,433,011 B2 (Kwana Patterson, Barbara Mitchell, Anand Mahadeshwar0: L’Oréal, Paris, has patented a method for treating chemically relaxed hair. It is comprised of applying a neutralizing composition to hair within 24 hours after a lanthionizing chemical relaxer composition has been rinsed from the hair. The neutralizing composition is comprised of at least 0.5 wt. % of at least one carboxylic acid selected from the group consisting of maleic acid, oxalic acid, malonic acid, malic acid, glutaric acid, citraconic acid, citric acid, glycolic acid, succinic acid, adipic acid, tartaric acid, fumaric acid, sebacic acid, benzoic acid, glyoxylic acid monohydrate, a salt thereof, and a mixture thereof; one or more C2-C6 monoalkanolamines; and water. The neutralizing composition remain son the hair for about 10 seconds to about 30 minutes and then, without rinsing the neutralizing composition from the hair, a neutralizing conditioner is applied. The neutralizing conditioner contains at least 0.5 wt. % of at least one carboxylic acid selected from the group consisting of maleic acid, oxalic acid, malonic acid, malic acid, glutaric acid, citraconic acid, citric acid, glycolic acid, succinic acid, adipic acid, tartaric acid, fumaric acid, sebacic acid, benzoic acid, glyoxylic acid monohydrate, and a mixture thereof; one or more C2-C6 monoalkanolamines; one or more cationic surfactants; and water. The neutralizing conditioner remain on the hair for about 5 minutes to about 30 minutes. The final step is to rins the neutralizing conditioner and the neutralizing composition from the hair.