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.
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