LATENT IMAGE COMPOSITE MASTER AND METHOD

摘要

In the disclosed method for making a composite master capable of producing both visible and invisible images on a copy or receptor sheet, a first and second set of infrared absorptive images are entered on the obverse, uncoated surface of the master and mirror image deposits of dithiooxamide (DTO) or a derivative thereof corresponding to the second set of images are entered on the reverse surface of the master. The reverse surface is coated with a dye precursor such as a gallate. A wax transfer sheet or the like is used for providing the DTO deposits. The resulting master is capable of providing both visible and invisible entries on a nickel or copper salt-coated receptor sheet by passing the master and receptor through an infrared copying machine.