USSS International Ink Library
Definition
A collection of ~10,000 dated writing ink formulations maintained by the United States Secret Service since 1968, providing a terminus post quem (earliest possible application date) for any ink whose formula matches a dated library entry.
- Established
- 1968 by the United States Secret Service
- Size
- Over 10,000 ink formulations
- Coverage
- 130+ manufacturers across 50+ countries
- Primary use
- Chromatographic and spectroscopic dating of questioned documents
Common questions
What does the USSS International Ink Library contain?+
It's a reference collection of over 10,000 dated writing ink formulations from more than 130 manufacturers across 50+ countries. The library holds chromatographic and spectroscopic data for each ink, making it a research tool for identifying and comparing questioned inks in forensic casework.
How does the library help date a document?+
When an ink from a questioned document matches a dated entry in the library, the match establishes a terminus post quem (earliest possible application date). This means the document could not have been written before the date the ink formula first appeared in commercial use.
When was the USSS International Ink Library established?+
The United States Secret Service created and began maintaining the library in 1968, building it over decades into the large reference collection used in forensic ink analysis today.
Related terms
- Iron-Gall Ink
- A historical ink formulation of ferrous sulphate, tannic acid (from oak galls), and gum arabic. The ferrous-tannate complex oxidises to brown ferric-tannate...
- ASTM E2285 / E2286
- The two ASTM International standards governing forensic ink examination: E2285 covers TLC-based ink alteration examination; E2286 covers HPLC-based ink comparison. Both are...
- Ballpoint Ink
- An oil-based, high-viscosity ink using a resin binder (alkyd or polyamide) in a high-boiling solvent (phenoxyethanol or benzyl alcohol), with triphenylmethane dyes...
- BKA Ink Reference Collection
- The Bundeskriminalamt (German Federal Criminal Police Office) reference database of European pen ink formulations, used as the evidentiary baseline for questioned-document cases...
- Carbon Black
- A colloidal carbon pigment produced by incomplete combustion; the primary colourant in permanent black gel inks, Indian inks, and archival drawing inks;...
- HPLC-DAD
- High-performance liquid chromatography with diode-array detection. Separates ink dyes on a C18 column and records UV-visible spectra at each elution point, providing...
- Ink Tagging Programme
- A voluntary scheme begun in 1979 whereby participating pen manufacturers add annual chemical tags (rare-earth chelates or fluorescent markers) to their formulations;...
- Manufacturing Change Window
- The interval between when an ink formulation was introduced and when it was discontinued or reformulated; documents with ink outside this window...
- Phenolic Resin
- A class of synthetic polymer binder formed by condensation of phenols with formaldehyde; used in ballpoint ink vehicles since the 1950s; identifiable...
- Phenoxyethanol
- The primary high-boiling solvent in most modern ballpoint ink formulations. Its progressive evaporation from the dried ink film after writing is the...
- Phenoxyethanol (2-Phenoxyethanol)
- A semi-volatile high-boiling solvent that constitutes a major component of ballpoint ink vehicles; its gradual loss from the dried ink film after...
- Raman Microspectroscopy
- A vibrational spectroscopy technique using a focused laser beam to excite molecular vibrations in an ink sample. Non-destructive. Primary method for toner...
Explained in these topics
- Ink Chemistry: TLC, HPLC, Raman and the Video Spectral Comparator WorkflowA collection of ~10,000 dated writing ink formulations maintained by the United States Secret Service since 1968, providing a terminus post quem (earliest poss...
- Ink Classification and Chemistry: Ballpoint, Gel, Fountain and MarkerThe United States Secret Service's reference collection of over 10,000 ink entries from more than 130 manufacturers in 50+ countries, established 1968; provide...