From 1900 (there was an earlier company) W & N set up as lithographic (stone) printers, prooducing calendars, playing cards, gift books, postcards, paper dolls, advertising items etc. Here is a picture of one of their lithographic presses.
Through later acquisitions, boxes and bulk packaging were also produced.
"Wenau" (from the initial letters of Wezel and Naumann) seems to have been the "brand" used by W&N on its own postcards, eg series Wenau - Brabant, Wenau - Pastell etc.. The cards also have the printed or symbolic "W&N" logo.
The firm closed in 1956.