The guy appears to be "Big Jack", as seen in old advertising at this site: http://union-made.blogspot.com/2012/12/1940s-big-jack-manufacturing-co-ink.html
Didn't they have a coverall or blue jean with the "Big Jack" button on it. Nice ID nhbenz.The guy appears to be "Big Jack", as seen in old advertising at this site: Union-Made: 1940s Big Jack Manufacturing Co. Ink Blotter