ASTM E2285 / E2286
Definition
The two ASTM International standards governing forensic ink examination: E2285 covers TLC-based ink alteration examination; E2286 covers HPLC-based ink comparison. Both are produced by ASTM Committee E30 on Forensic Science and aligned with SWGDOC guidelines.
- E2285 method
- TLC (thin-layer chromatography) for ink alteration
- E2286 method
- HPLC (high-performance liquid chromatography) for ink comparison
- Issuing committee
- ASTM Committee E30, Forensic Sciences
- Aligned with
- SWGDOC guidelines
Common questions
Why does ink examination use two different chromatography techniques rather than one?+
TLC under E2285 is fast and well suited to detecting alterations such as added or substituted entries, while HPLC under E2286 offers finer separation for comparing dye and pigment formulations between two ink sources, so the two methods serve different investigative questions within the same discipline.
Does either standard let an examiner date when ink was written?+
Neither E2285 nor E2286 is an ink-dating method; they address alteration detection and source comparison respectively. Ink dating relies on separate volatile-component-decay methods and different guidance, such as ASTM E2494.
Related terms
- 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...
- 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...
- 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...
- Phenoxyethanol
- The primary high-boiling solvent in most modern ballpoint ink formulations. Its progressive evaporation from the dried ink film after writing is the...
- 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...
- TLC (Thin-Layer Chromatography)
- A planar chromatography technique on silica gel plates that separates ink dye mixtures by polarity. ASTM E2285 governs its forensic application. The...
- Toner
- A dry-powder printing material consisting of fine styrene-acrylate polymer particles carrying carbon black and organic pigment, electrostatically applied and thermally fused at...
- USSS International Ink Library
- A collection of ~10,000 dated writing ink formulations maintained by the United States Secret Service since 1968, providing a terminus post quem...
- VSC (Video Spectral Comparator)
- A multispectral imaging instrument used in document examination; illuminates the document at multiple wavelengths (UV, visible, near-IR, IR) and captures fluorescence and...