Install brother-lpr-drivers-mfc9420cn by entering the following commands in the terminal:
sudo apt update sudo apt install brother-lpr-drivers-mfc9420cn
Description:
LPR driver for mfc9420cn brother printer
This package provides LPR driver for model MFC-9420CN
Homepage: http://solutions.brother.com/linux/en_us/
Version: 1.0.0-3-0ubuntu4
Section: multiverse/text