A study to investigate the evidential value of blue and black ballpoint pen inks in Australia

Abstract The aim of this project was to investigate the evidential value of blue and black ballpoint pen inks in Australia. For this purpose, 49 blue and 42 black ballpoint pen inks, of different brands, models and batches, representative of those ballpoint pens available on the Australian market at the time of the study, were analysed by three techniques: filtered light examination (FLE); reflectance visible microspectrophotometry (MSP); and thin-layer chromatography (TLC). The results showed that the power of the individual techniques to discriminate inks between and within brands, models and batches varied, the most informative techniques being TLC>FLE>MSP. The greatest degree of differentiation was achieved when using a combined sequence of techniques, the discriminating power being 0.99 and close to 1 for blue and black inks, respectively (different brands and models). In respect to the discrimination between different batches of a same brand and model, it was shown that 14 out of the 33 pairs compared could be discriminated. Overall, this study confirmed the high value of the examination of inks when applied to ballpoint pens available in Australia, especially when a combined sequence of techniques is applied.

[1]  Laser Examination as an Additional Nondestructive Method of Ink Differentiation , 1988 .

[2]  Ah Lyter.  Examination of Ball Pen Ink by High Pressure Liquid Chromatography , 1982 .

[3]  D. K. Laing,et al.  The Comparison of Nanogram Quantities of Ink Using Visible Microspectrometry , 1983 .

[4]  S. P. Day.  Evaluation of the Application of the Argon-ion Laser to Document Examination: A Review of Casework and Experimental Data , 1985 .

[5]  A rapid infrared luminescence method for differentiation of ink writing , 1980 .

[6]  C Jaccard.  The Differentiation of Writing Inks Using a Sequence of Optical Examination Techniques. , 1996 .

[7]  A rapid identification of black colour materials with specific reference to ballpoint ink and Indian ink , 1988 .

[8]  A C Moffat,et al.  The calculation of discriminating power for a series of correlated attributes. , 1973, Journal - Forensic Science Society.

[9]  S. K. Gupta,et al.  Ink Differentiation with Infrared Techniques , 1973 .

[10]  Larry K. Nelson,et al.  An Evaluation of the Use of Laser-Induced Infrared Luminescence to Differentiate Writing Inks , 1991 .

[11]  C. Sensi,et al.  Infrared Luminescence: Is It a Valid Method To Differentiate Among Inks? , 1982 .

[12]  T. W. Sinor,et al.  Lasers and Optical Spectroscopy in Questioned Document Examination , 1986 .

[13]  Application of microspectrophotometry in document examination , 1983 .

[14]  Chromatographic Analysis of Inks for Forensic Science Applications. , 1991 .

[15]  Thin-Layer Chromatography of Writing Inks—Quality Control Considerations , 1996 .

[16]  Kelley Jd,et al.  Proposed Standard Methods for Ink Identification , 1975 .

[17]  A. Cantu,et al.  Some Spectral Observations of Infrared Luminescence , 1988 .

[18]  P. L. Kirk,et al.  Differentiation of Blue Ballpoint Pen Inks , 1961 .

[19]  A. Zeichner,et al.  Transmission and Reflectance Microspectrophotometry of Inks , 1988 .

[20]  A. Zeichner,et al.  Some Special Observations Regarding Visible Transmission Spectra of Inks and an Improved Method for Their Discrimination by Microspectrophotometry , 1992 .