Robert R. Mazer, an industrialist, philanthropist, longtime principal owner of the Chicago White Sox and for many years a Highland Park resident, died Friday. He was 90.

Born in Milwaukee in 1923, Mazer attended the University of Wisconsin where he majored in Chemical Engineering. He used that education to found Mazer Chemicals, a manufacturer of chemical emulsifiers and surfactants. The Gurnee Company employed 250 people.

In 1985, Mazer sold his company to Pittsburgh Paint and Glass and soon thereafter realized a lifelong dream of acquiring a substantial ownership interest in the Chicago White Sox, of which he became the largest individual investor and held a permanent seat on the Board of Directors.

During World War II, Mazer served as an electronic technician in a Navy division headquartered at the Great Lakes Naval Center.

Mazer and his wife, Claire Glantz Mazer, were founding members of both Congregation B'nai Torah and the Birchwood Country Club in Highland Park. They became frequent patrons and donors to many charitable and community service, as well as political, organizations. They played major roles in World ORT and its early development within the North Shore chapters of Women's American ORT, the American Society for Technion - Israel Institute of Technology, the American-Israel Public Action Committee, the Jewish United Fund, the International Fellowship of Christians and Jews and the Republican Party.

The Mazers were married for 56 years and she survives him. He was also the loving father of Dr. Neal (Zev Nathan) Mazer, Cliff Mazer, Julie Mazer and Leslie (Scott) Westfall. He was the proud grandfather of Ari Mazer, Amy Glasser, Eli Mazer, Benjamin Mazer, Mitchell Glasser, Corey Westfall, Ella Glasser and Andrew Westfall. He was the dear brother of the late Ed (the late Patches) Mazer, the late Adele (the late Harry) Bloom, the late Leo Mazer, the late Sylvia (John) Bensman and the late Bill (the late Fritzie) Mazer.