The New York Times reported Hartigan had earned a reputation for her vividly colorful artistic works that often were labeled pop art for their inclusion of many popular culture images.
But Hartigan never accepted that label for her works, saying the 1960s art movement did not truly capture the essence of painting, the Los Angeles Times reported Saturday.
"Pop art is not painting because painting must have content and emotion," the painter said in the past of the trend that had been led by the late artist Andy Warhol.
For Hartigan, her artistic goal was always to create order out of chaos.
"Somehow," she once said, "in painting I try to make some logic out of the world that has been given to me in chaos."
The New York newspaper said the "Summer Street" artist, who died last Saturday, is survived by a sister, a brother and three grandchildren.