Canon IMAGEFORMULA CR-190I Instructions Manual page 44

Press the Open Button, and push the Back Maintenance
Cover open to the back.
Wipe the feed path with a firmly wrung cloth, moistened
slightly with water or mild detergent. Then, wipe off with a
clean, dry cloth.
44
Feed Path
Close the Back Maintenance Cover.
Close the Front Maintenance Cover in the order shown in the
diagram below.