Many German postcard publishers include "Kunst" (Art) in their name but Erpaco seems to have only produced cards of paintings, perhaps most often figurative though one example card is a landscape. The legend round the logo, the "snake in the sun", means "Queen of the snakes". Some Erpaco cards also appeared in Tuck lists.
The cards typically have a heavy texture to imitate paint, which doesn't show up well in scans. The oblique photo of card 31 shows it better.
Erpaco 23-6
Erpaco 31
Erpaco 602b