Gundlach – who commenced, but never completed, a PhD at the University of Buffalo – is credited with making seminal contributions to the development of practical plain-paper copying technology. Key patents include US Patent No. 2,968,552, Xerographic Apparatus and Method, US Patent No. 3,738,855, Induction Imaging System, and US Patent No. 2,912,586, Xerographic Charging.
Gundlach also invented on his own time, both before and after retirement. His non-Xerox patents include US Patent No. 6,681,593, Thermal Eenergy Storage System, US Patent No. 4,345,439, Snowmaking Method and Apparatus, and US Patent No. 4,338,727, Shadowless Sundial.
Gundlach was inducted into the National Inventors Hall of Fame in 2005.
He died in New York of pneumonia on 18 August 2010. Vale and RIP.