Thomas L. Jennings
Thomas L. Jennings was born in 1791 as a free Black. He operated a hugely successful tailoring business in New York City. His store on Church Street was one of the largest clothing stores in the city.
Jennings noticed that customers would simply throw away difficult-to-wash clothes that became dirty. He invented a method of cleaning that fabrics that would preserve the clothing and get rid of dirt. We now call it dry-cleaning.
In 1820, Jennings applied for a patent for his dry-cleaning process. He was the first Black person in the United States to receive a patent.
Jennings became very wealthy from his method and used the money to fund abolitionism in the Northeast. In 1831, he became the assistant secretary for the First Annual Convention of the People of Color in Philadelphia, Pennsylvania. The convention was organized by a group of free Blacks to support the development of a Black nationalist political consciousness. They met a dozen times between 1831 and 1864.
Jennings died in 1859.
Sources:
http://www.blackinventor.com/pages/thomas-jennings.html
http://www.blackpast.org/?q=aah/national-negro-convention-movement-1831-1864