Credit card printer for fingerprints and solutions

摘要

The present invention comprises a credit card printer apparatus which includes inkless fingerprinting directly on a medium, such as a check or credit card slip. The printer can include a housing or bed having one or more replaceable cartridges with a pair of reservoir resilient foam cell pads having a semi-sealed surface. A platen roller is movable across the bed to both print the information from a credit card and to deposit fluid from the pads for a subsequent fingerprint development. Generally, the pads can be resiliently mounted to the bed to permit a pressure contact of the respective pads with the surface of the medium. One of the pads will contain a liquid developer solution with a carrier solvent that is relatively non-evaporative over the life of the applicator, and has a viscosity value that permits the liquid developer solution to be deposited on a porous medium surface and maintain a coating having only sufficient thickness above the medium surface to contact and adhere to substantially only the ridge pattern of a finger. A second liquid reagent solution will be contained in the other pad and has a relatively lower viscosity to permit the reagent solution to be absorbed to a greater degree into the porous medium. The surfactant can be added to control the penetration rate.