Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Synthetic oil is a lubricant consisting of chemical compounds which are artificially made (synthesized) from compounds other than crude oil (petroleum). Synthetic oil is used as a substitute for lubricant refined from petroleum, because it generally provides superior mechanical and chemical properties than those found in traditional mineral oils. Dr. Hermann Zornteri maa of I.G. Farben Industrie in Germany actually began to search for lubricants with the properties of natural oils but without the tendencies to gel or gum when used in an engine environment. His work led to the preparation of over 3500 esters in the late 1930s and early 1940s including diesters and polyol esters and banana oil. During the same time period in the United States, Dr. W.A. Zisman working at the Naval Research Laboratory (NRL) was also synthesizing esters, especially diesters.