You know blue collar, white collar. Silk collar is when Westerners, typically Americans, move to Asia for work and better opportunities. The term was first used by silkcollar.com staffing agency.
"I've been blue collar, white collar, and when the US economy crashed, I'm rocking silk collar here in China"
"I couldn't get any decent job after college so I moved to China for a silk collar job, teaching English"