The poplin is a 'business' fabric, very strong, with a corded surface. This kind of fabric is made of fil-à-fil and the pinstripe.
It's quality is from 100/2 to 240/2.
Historicaly, this fabric was called "papelino", because it was produced for the pope in Avignon, in France.
Poplin Pinstripe
Poplin Fil à Fil