Abstract: A method and apparatus for improving the optical boundary between a person's fingerprint ridges and the surface platen of a live-scan-imaging apparatus includes providing an absorbent pad containing chemicals selected from the nonvolatile oils, oil amides, fatty alcohols and fatty acid esters, placing the person's finger to be scanned on the surface of the absorbent pads to coat the fingerprint ridges and subsequently placing the person's finger with the coated fingerprint ridges on the platen of the imaging apparatus to provide a high contrast between the ridges and valleys of the fingerprint area.

Abstract: A fingerprint ink dispensing apparatus includes a ceramic disk positioned over an ink reservoir in the form, for example, of a felt pad. The ceramic disk has an average porosity of about 40% and an average pore size of about 5 microns. A colored pigment such as carbon black dispensed in a hydrocarbon oil is disposed in the reservoir with the concentration of the carbon black being about 22% by weight and the diameter of the carbon black particles falling within the range of 0.15 to 0.60 microns and the average size being about 0.35 microns.

Abstract: An inkless method of recording an image of a desired object or symbol such as the print of a person's finger is described in which a recording surface is prepared by placing thereon a thermosensitive color-developing layer comprising a chromogenic dye such as a leuco dye, an organic acid developer, such as a phenolic compound, reactive with the dye to form a color and a thermosensitive barrier layer separating the dye and developer. A chemical reagent containing one or more metallic slats, such as ferric chloride, in the format of the desired object or symbol, is applied to the recording where the reagent reacts with the developer and/or dye in the thermosensitive color-developing layer to form a permanent two-dimensional image of the object or symbol such as the ridge pattern of the person's finger.

Abstract: A method for enhancing fingerprint images comprises the steps of applying a chemical compound to the fingers to be printed in which the compound contains a first constituent in the form of a conventional ink or inkless reagent. The first constituent is arranged by itself (i.e., ink) or in conjunction with a developer (i.e., inkless) to provide a visible image of a fingerprint when applied to a porous surface, such as a conventional fingerprint card under light within the visible spectrum. A second constituent is included in the compound which is arranged to fluoresce within the visible spectrum (i.e., 500 to 650 nm) when subject to U.V. radiation, preferably centered at 550 nm.The compound from the fingers is then deposited onto a porous surface and a visible image is formed therefrom representing the ridge patterns of the fingers. The surface is then illuminated with visible and ultraviolet light and the fluorescence of the second constituent enhances the brightness of the image.

Abstract: 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.

Abstract: The present invention comprises an apparatus for inkless fingerprinting directly on a medium, such as a check. The apparatus can include a stamp housing having a replaceable cartridge with a pair of reservoir resilient foam cell pads having a semi-sealed surface. One of the pads will contain a liquid developer solution, for example, a water soluble inorganic compound; while the other pad will contain a liquid reagent solution, for example, a water soluble inorganic compound which can react with the liquid developer solution to deposit a non-soluble colorant precipitate. Advantageously, the liquid developer solution will include 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.