US Patent No. 9,872,821 B1; Liqwd, Inc.
, Santa Barbara, CA, has patented a method of curling. The method comprises applying a formulation comprising one or more hydroxide-containing agents; and one or more active agents selected from the group consisting of maleic acid, acrylic acid, methyl acrylic acid, and vinyl sulfonic acid, and simple salts thereof to the hair; and reshaping the hair. The method is substantially free of a sulfur-containing reducing agent.