UCSB Science Line
Sponge Spicules Nerve Cells Galaxy Abalone Shell Nickel Succinate X-ray Lens Lupine
UCSB Science Line
Home
How it Works
Ask a Question
Search Topics
Webcasts
Our Scientists
Science Links
Contact Information
What method is the best for preserving fingerprints?
Answer 1:

The preservation of the different types of fingerprints are affected by exactly what material they were left behind with.Here it might be helpful to discuss the difference between "patent," "latent," and "plastic" fingerprints. With patent you would have a visible impression on a surface left with some other material, such as flour or oil. Latent isn't necessarily visible by the human eye. Lastly, plastic fingerprints are 3- D, "molded" prints left in a material, such as putty.

Fingerprints fresh enough to still contain water (< 24 hours old) can also be preserved with superglue (ethyl cyanoacrylate). Super glue liquid is made up of many molecules of ethyl cyanoacrylate. When it is exposed to air, the moisture in the air will cause it to polymerize, meaning that all of the molecules react together to form chains. If fingerprints are exposed to ethyl cyanoacrylate vapor, the ethyl cyanoacrylate will react with the moisture in the fingerprint and polymerize on the ridges of the fingerprint, forming a hard surface and preserving it.



Click Here to return to the search form.

University of California, Santa Barbara Materials Research Laboratory National Science Foundation
This program is co-sponsored by the National Science Foundation and UCSB School-University Partnerships
Copyright © 2015 The Regents of the University of California,
All Rights Reserved.
UCSB Terms of Use