Abstract Expressionist paintings that employ large areas of color such as Mark Rothko's Blue, Orange, Red are also known as:

Color Field Painters

Explanation:

Color Field is an abstract expressionism painting, largely painted on the flat area with thick paint into canvas, creating an unbroken surface. Color Field painting requires less stress on brushstrokes and perfection. This painting evokes aesthetic and emotional responses. The style of painting began in New York during the 1940s - 50s and later spread to different counties.