Substrate having colored indicia thereon for read-out by infrared scanning apparatus
US3933094A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 1973 |
| Grant date | Jan 20, 1976 |
| Priority date | — |
| Expiry date | Nov 19, 1993 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S209/90
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
In a method for making a business reply envelope having binary bar code indicia imprinted thereon for identification or read-out by infrared scanning apparatus, the steps of providing a plurality of printing inks, each of said inks being of a color which in combination with the envelope substrate yields a Print Contrast Signal substantially less than 50 percent when measured in the wavelength range of 800 to 900 nanometers as determined by the equation Print Contrast Signal = Rw-Rb/Rw .times. 100 wherein Rw is the percentage reflectance of the unprinted substrate of the envelope and Rb is the percentage reflectance of the printed area of the envelope, adding a material comprising a metallic compound to only one of said inks in quantity sufficient to increase the Print Contrast Signal of said one ink color and said substrate to at least 50 percent, imprinting at least said indicia on said substrate with said one ink, and imprinting further material on said substrate with the other of said inks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.