When did Bob Wieland sell the dairy?

Where can you find information on Wieland's Dairy in Chicago?

The Wieland Dairy and Ice Cream Factory, (in Chicago), was developed by my great grandparents, Jacob and Gottlieben (Gleich) Wieland. They came to the USA in 1889, bringing along their 7 sons,1 daughter, and Jacob's father. The Wieland Dairy was very successful, as was the Ice Cream Factory, where the "Good Humor" ice cream bar was developed. In the early 1930's the dairy was sold, for $8.5 million to "Borden", hence the name "Wieland/Borden Dairy" on all the bottles, for a period of time, (stipulated in the sale), later becoming just "Borden". The money was divided equally between the the sons and daughter. Two of the sons were against the sale, so they started CJ Wieland & Company Dairy. Not knowing whether this is a genealogy question or a question about the dairy itself, I welcome all to contact me. My father was eventuallya partner in the C.J Wieland Dairy and the chief chemist developing the formulas for the products. The Dairy was eventually sold to Hawthorn Melody in 1951. I would LOVE any photos anyone has of the dairy such as someone said they had. C.J. Wieland had an ice cream parlor and was regarded as the premium brand in Chicago. The aidry products were sold both in many markets and by home delivery.