By Jeffrey Calta
Rudolf was elected president of L. Sonneborn & Sons in 1934 after Ferdinand retired from operational control. Rudolf’s weekend life in the early years of WW2 was usually spent in Baltimore at his mother’s residence. His bachelor status, wealth, and handsome appearance enabled Rudolf to have a busy dating life. He was often seen around Baltimore with Hollywood and stage actresses. One beauty in particular was Jessie Landis. Jesse was an accomplished stage actress but is best known for appearing in Alfred Hitchcock’s To Catch A Thief and later played Cary Grant’s mother in North By Northwest. Jessie and Rudolf were often seen in newspaper society pages from 1942 through 1945. However, they never married. Rudolf did eventually marry Dorothy Schiff the editor and owner of the New York Post newspaper. They began dating in 1951 and married several years later. Dorothy would remain his wife until 1960.
After WWII, there was an international surge of interest in giving Jewish people a homeland in the land of Palestine. Rudolf Sonneborn was a central figure in raising funds to keep the fledgling state of Israel functioning. The Sonneborn Institute was created to provide logistical and financial support for Israel and Rudolf is generally acknowledged as one of several individuals who made the modern state of Israel possible.
The 50th anniversary of the company was coming in November, 1953 and Rudolf was planning a big celebration for the event. He brought Dr. Hans Schindler, manager of the Petrolia plant and Dr F. W. Breth, vice president and technical director to New York to plan the event. L. Sonneborn & Sons had grown considerably in the period after WW2. The research arm under Dr Breth’s guidance had broadened the company’s product slate while making constant improvements in the white oil and petrolatum processing. Sonneborn products now included materials used in building construction and maintenances and in leather processing and waterproofing of paper. Rudolf had his media staff prepare a 36-page brochure for distribution during the event. Its cover featured a 3-D photograph of a petroleum sulfonate molecule.
The brochure also included many of the company’s specific accomplishments: Development of the first additive to keep lube oils from freezing, a new and more practical way of making microcrystalline wax in slab form for easier handling, and the use of Bauxite clay for a more efficient filtering media for petrolatums. The use of Vitamin E as a white oil preservative was also a Sonneborn exclusive discovery. A line of water-soluble detergents was developed and sold under the name of Whistlclean. It was found to be an excellent cleaner for many industries such as baking, textile, and flooring materials. The growing use of concrete in the post- WWII era offered yet another outlet for its products. Sonneborn researchers developed a chemical process which gave concrete many times its original hardness. This product was known as lapidolith. This breakthrough was soon followed by the development of material for weatherproofing brick masonry and for wood preservation.
Rudolf Sonneborn suffered a serious stroke in May, 1959 while in New York City. He was left unable to walk or speak for many weeks but began to improve slowly. This turn of events had an immediate effect on the company. Henry Sonneborn III, grandson of the clothing manufacturer in Baltimore was installed as president of L. Sonneborn & Sons. Very soon after Rudolf’s stroke, an offer to purchase the company was made by William and Robert Wishnick of Witco Chemical Corporation. The offer was accepted by the Sonneborn management and the business became part of Witco Chemical Corporation in 1960. Rudolf did improve slowly from his stroke but was unable to fully participate in the business affairs of the new company. The rest of his life was spent in philanthropic pursuits and endless honors for his many achievements. He passed away on June 1, 1986 at his estate in Danbury Connecticut.