Printing ribbon for printing red scannable bar codes

Abstract

A printing ribbon for printing bar codes which appear visibly red and are scannable by conventional bar code scanning systems utilizing lasers emitting light having wavelengths in the visible red region and collectors which collect the light reflected from the bar codes. This is accomplished by the provision of a printing ribbon having a printing medium adhered to a backing element. The printing medium preferably includes an interspersed distribution of pigments which are retained in a binder. These pigments can include a combination of red coloring agents, such as visible red pigments which visibly appear red under broad spectrum light, fluorescent pigments which are inactive under light having wavelengths in the visible red region, but which fluoresce under broad spectrum light, and red absorbing agents, such as visible black or other dark colored pigments. The fluorescent pigments are activated under broad spectrum light and act to shield or mask the dark color of the visible black or other dark colored pigments, thus making the printed image appear red in broad spectrum light. This results in printed bar codes which appear visually red under broad spectrum light, yet are scannable by bar code scanning systems utilizing lasers emitting light having wavelengths in the visible red region and collectors which collect the light reflected from the bar codes.