ROCHESTER, N.Y.-Aug. 6, 2002--Robert W. Gundlach's 155th U.S. patent for Xerox Corporation, granted in late July, marks the culmination of an extraordinary five-decade-long creative collaboration - an inventive mind merged with an environment that both fosters and depends on innovation. One of the world's most productive living inventors, Gundlach, 75, also holds more patents than any other individual in Xerox history. The latest patent, No. 6,424,364, covers an inkjet printing process that can achieve a glossy photographic-like surface on plain paper. When Gundlach retired from the company in 1995, 12 applications for patents had been filed; this is the last of the patents to issue. Inventions associated with his hobbies have added another eight, bringing his total to 163 U.S. patents. "Bob's contributions to Xerox - and the entire printing and copying industry - have been remarkable," said Herve Gallaire, president, Xerox Innovation Group. "Only a few people in the world hold so many patents. His inventions through the years have made possible many technologies the world takes for granted today, starting with things as basic as desktop copiers, the reproduction of solid areas of images, and simplified image development." It was the latter - one of the first inventions Gundlach made shortly after he started working for Xerox's predecessor, The Haloid Company -- that caused Chester Carlson, the inventor of xerography, to say to him, "Bob, you're an inventor." Gundlach says modestly that about half his patents were based on lucky accidents and the other half on recovery from failure, but he credits the foresight of Xerox management for "creating an environment where research is valued and inventions can happen." "I will be forever grateful for Xerox's support of exploratory research," Gundlach said. "I didn't have to apologize that not everything worked. The management understood that only 10 percent of the exploratory research might work out, but that 10 percent represented the future of the company." Gundlach was a 26-year-old physicist from Buffalo, N.Y., in 1952 when he joined Haloid, a Rochester manufacturer of photographic papers that was trying to commercialize a new process, known as xerography, for making copies. There were only 85 people actively engaged in research and engineering for both xerographic and photographic products at the time. Today Xerox has thousands of scientists and engineers and spends about $1 billion a year on its research and development efforts. Gundlach began contributing immediately. In his first year he conceived three patentable inventions, one of which made it possible to create metal masters for offset duplicating -- a problem that had stumped a half-dozen other researchers for three years. That innovation enabled Haloid to develop a timely product for the European market and was one of the incentives for the formation of Rank-Xerox, later Xerox Europe. By the time Haloid Xerox introduced the world's first automatic plain-paper copier (the Xerox 914) in 1959 and started a revolution in office communications, Gundlach had developed a company-wide reputation as an extremely imaginative inventor whose real gratification came from developing ideas that could be put into use to serve people. In 1963 Xerox created a program to provide promotional opportunities for individual contributors, and Gundlach was one of its first four Senior Scientists. In 1966 he was named Xerox's first Research Fellow, at that time the highest non-managerial post that could be achieved by a Xerox scientist, and in 1978 he was appointed Senior Research Fellow. Gundlach's expertise was exploratory work in imaging methods, mostly xerographic. His 155 Xerox patents cover innovations in the areas of developing methods, fusing processes, cleaning methods, optical systems and charging systems. "People have always underestimated the growth potential of xerography," Gundlach said. An avid outdoorsman who still runs 1.5 miles a day, Gundlach was returning from a ski trip when the inspiration came for what would be his final Xerox patent. He and his son Kurt, who also worked for Xerox and is one of the co-authors, were discussing the growing use of inkjet printers and the cost of papers required to produce special effects such as glossy colored pictures. Their idea: to use a transparent toner to undercoat only the areas that would be printed on, print by inkjet over the coated areas, then put the paper through a xerographic fuser to fix the image. One of Gundlach's most significant inventions was "tri-level xerography," a xerographic process that permits printing in two colors in a single pass, thus achieving perfect registration and greater speed than competitive methods. That invention was the basis of a successful line of Xerox highlight color printers, widely used to print bills and invoices, which was introduced in 1991. With typical humility, Gundlach shares the credit with a team of some 200 Xerox scientists and engineers who brought the product to market. Today, the imaging industry he helped create produces 8 billion to 9 billion xerographic prints or copies every business day, according to Xerox estimates. Reflecting on his time at Xerox, Gunlach said, "I have enjoyed a professional lifetime filled with the challenges and deep satisfaction of being part of a company that substantially changed the world."