Ink Analysis Lecture Notes
What is in ink?
· Several organic dyes - blue, red, black,
etc. (This can form an ink "fingerprint.")
· Tags that signify the manufacturing year - isotopes
Why is ink important forensically?
· Fraud cases
· Kidnapping and Ransom
How is ink used as a forensic tool?
· A small sample is dissolved.
· This sample is compared to a known sample.
· Each pen manufacturer has its own "recipe" for ink,
so a sample from a document can lead to the discovery of the type of
· The tags in ink can determine the year the pen was manufactured.
What is thin layer chromatography (TLC)?
· Qualitative analysis.
· Separates mixtures into individual parts.
· "Like dissolves like" - polar vs. non-polar.
· Mobile phase vs. stationary phase.