The reason Enjay Chemical was named that was because Standard Oil of New Jersey (Esso) only had rights to that name in certain states...in all actuality they were Esso Chemical; but couldn't operate under that name in most of the states. The original Standard Oil companies owned the rights to that name in their territories...Socony-Vacuum (Mobil) was Standard/New York; American Oil Company (Amoco) was Standard of Indiana, Standard of California was Chevron, Standard of Kentucky was KYSO, Standard of Ohio was Sohio, etc etc. Growing up in Missouri, the Standard station was Standard of Indiana. They all had an interoperable credit card system back in the 40s/50s/60s until they started to merge and create national retail footprints. The last truly interoperable card was Sohio, who maintained their agreements with all of the original Standards. My dad had tins of epoxy glue in the work room which were labeled Enjay (must have been from roughly 1970 right before Exxon).