thank you for the question hope this helps
Sometimes she would use a hot comb but did NOT invent it. Still, she was the first person to use these methods
Walter Sammons of Philadelphia, Pennsylvania received U.S. patent #1,362,823 on December 21, 1920 for an improved comb that straightened hair. According to Walter Sammons' patent he invented a heated comb that removed kinks from the hair.
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