Two-part inkless applicator for fingerprints
US4029012A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 1975 |
| Grant date | Jun 14, 1977 |
| Priority date | — |
| Expiry date | Dec 18, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S283/901
- WIPO fieldMedical technology
- WIPO sectorInstruments
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. 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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.