Most food cans are not coated on the outside; rather, paper labels are used. The
appearance of coated and printed cans is more attractive than paper labels. Some
food and all beverage cans are coated and printed. Printed metal cans are not
affected by water such as from ice chests or condensation when cans are
brought out of a refrigerator into humid air.
The general procedure used on the exterior of sheets for bodies of three-piece
cans is to apply a base coat, often called enamel, print on the base coat up to
four colors by offset lithography, and finally top coat with a finishing
varnish. The most common color for base coats is white, but a variety of color
is used for specific products. Color stability and lack of color change on
backing are critical requirments.