Can a UPC Bar Code Be Printed in Color Ink or on Colored Paper?

Article ID: 00104286

Question

Can a UPC Bar Code Be Printed in Color Ink or on Colored Paper?

Facts

Many large retail chains now fine or disqualify vendors who supply products with bar codes that do not scan. If you print a UPC symbol with color ink or on a colored background, you run the risk that the symbol will not scan.

Answer

Color ink and/or colored paper will reduce the contrast between the bars and spaces of a bar code.  Also remember that virtually all scanners use red light.  If you print the bars using any shade of red, the same amount of light will reflect off the red bars as the white spaces.  Printing black bars on a colored paper will reduce the light reflecting off the spaces and reduce the contrast.  Other colored inks will also reduce the contrast ratio between the bars and spaces and greatly increase the probability of an unreadable bar code.  If the black bars and white spaces are too glossy, the symbol also may not read.  An example of this would be to print black bars on a silver can.