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.