Abstract
A calibration test is described for monitoring the operation of equipment used to develop latent fingerprints on thermal paper by the application of either controlled or uncontrolled heat. A working solution of a water/glycerol emulsion and butylene glycol is applied to thermal paper by means of either a vinyl stamp and pad, or a marker pen. Varying the amount of butylene glycol enables the thermal paper to change color at different temperatures between approximately 40 and 60°C, which is below the normal color change temperature of the paper. The described test may be used to verify the correct operation, at different temperatures, of a controlled heat source during and after fingerprint development (such as the Hot Print System) or to monitor the paper temperature with an uncontrolled heat source (such as a warm air blower), thereby avoiding unintentional coloring of the entire paper surface.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.