Edwin Cowles (1892-1968)
2000 Paper Industry International Hall of Fame Inductee
Cowles Chemical Company
and Cowles Engineering Corporation
Sewaren, New Jersey, U.S.A.
Edwin Cowles was born in Cleveland, Ohio, and educated in the Cleveland school system. He earned a degree in marine architecture at Cornell University, Ithaca, NY.
Cowles founded Cowles Chemical Company in 1925 in Cleveland, Ohio, and Cowles Engineering Corporation in Sewaren, New Jersey, in 1930. He was a consultant and inventor for the Downingtown Paper Company in Downington, Pennsylvania from 1930 to 1938, and for Dilts Machine Works in Fulton, New York, from 1939 until his death in 1968.
Cowles invented a method of pressure screening and of defibering paper fibers, known as the “Classifiner”, prior to 1939. All modern screening via pressure screening, now combined with completely automated reject control, derives from his work. Cowles also invented and developed the Cowles Pulper, which was patented in 1944. This later became known as the “Hydrapulper (TM)”, a product of Dilts Machine Works, Fulton, NY. The Dilts company became a division of the Black Clawson Company in 1940 and later a division of Thermo Fibertek, Inc. In the 1930s and ’40s, the U.S. paper industry was considerably ahead of Europe and Asia because of Cowles’ inventions. After World War II, Black Clawson exported this technology worldwide. Today, all modern defibering of virgin and secondary fibers is done in an hydrapulper, or copy equivalent, totally controlled by advanced instrumentation. In his varied career, Cowles also invented laundry processes and equipment, and laundry chemicals, particularly silicates and stearates.
Cowles’ inventions greatly improved the quality and uniformity of fibers leading to improved paper machine efficiencies. Other additional advantages were decreased energy consumption and increased efficiency in the use of broke, waste papers and other grades of secondary paper. Thus, the door was open for the use of municipal solid waste as a source of fiber.
Cowles received 40 patents on his inventions. He was a member of the Technical Association of the Pulp and Paper Industry (TAPPI) from 1940 until his death in 1968 in New York City. His is buried in Cleveland, Ohio.