Swan Soap

Swan was a brand of soap introduced by the Lever Brothers Company in the United States in 1941 to compete with Ivory.

Still, Lever had developed and patented a new manufacturing method that streamlined the process and resulted in a finer product, more like milled soap.

and Lever sued Procter & Gamble for patent infringement after the format of Ivory changed; the appellate court[where?][which?]

She testified that a week or two after she started using Swan, the detergent dried out her fingers, and they began to itch around the nails.

When her nails began to recede within two or three months, Mrs. Young reflected upon the cause and theorized that the change to Swan could have been responsible for the condition.