Printing Process Determination

PRINTING INK

Counterfeit documents are often produced by commercial printing, usually utilizing the offset printing process but sometimes also using the typographic or intaglio processes. The ink used in the production of these documents may be compared with inks on other like documents, with inks in containers found at print shops, or with inks found on counterfeit paraphernalia such as printing presses, offset plates, etc. In order to conduct these analyses, fairly large samples (approximately 1/4″ circle) must be taken from the documents in question.

EXPECTED RESULTS

A determination can be made as to whether the ink(s) on documents in question and the inks from known sources (such as ink containers, offset plates, et cetera) are the same or different.

SUBMITTER’S RESPONSIBILITIES

All evidence should be inventoried and submitted with a request letter. Samples of printing ink may be submitted in small vials or in cans. Specify the ink and/or documents to be compared.

Office Machine Analysis

OFFICE MACHINE COPIERS

In recent years the office machine copier “OMC” industry has expanded enormously. Not only has the demand for copiers increased, but the technology has expanded outside the standard office copier. This growth is seen in the full color copiers, ink jet copiers, digital stencil duplicators, thermal printers, laser printers and multi-purpose machines. With the ease of use and accessibility of these machines, the use of OMC’s for fraudulent activities has increased dramatically.

EXPECTED RESULTS

A microscopic and/or chemical examination may reveal the type of process used to print the document. This can then be compared against the process(es) used to produce genuine or unaltered documents to aid in determining authenticity.

As a copier is used, defects occur from scratches on the platen (the glass where the original document is placed), the document cover, the photoreceptor (the charged drum inside the copier) or the fuser rollers (the rollers which fuse the toner to the paper). These defects may be visualized on the copy. A defect, or “trash mark”, comparison can be made between questioned copies and suspect machines; and it is possible to identify a specific copier as being the copier on which the questioned copies were made.

If identification cannot be made, it is still possible to make a comparison of class characteristics to confirm or eliminate the possibility that the copier could have been used in the production of the copy. At times “trash marks” may be used in conjunction with machine service records and documents known to have been copied on given dates to determine the approximate date a specific document was copied or to determine that a document could not have been copied on a given date.

SUBMITTER’S RESPONSIBILITIES

Documents submitted for copier or printer analysis should be submitted for document analysis prior to submitting for latent print examination. When a copier is suspected in making the questioned documents, samples should be taken as soon as possible. Defects change with use, so time is often a factor in the ability to identify the suspect machine. Toner may also be depleted and replenished with use, sometimes making a chemical analysis of questionable value.

In obtaining samples, several sets should be taken. A set should contain multiple (seven to ten) copies of each paper size available for the machine. Each set should be stapled together and labeled as to how they were produced; which side is the image side; the make, model and serial number of the machine; and initialed and dated.

The first set should be taken with a clean white sheet of paper on the glass the same size as the copy size. The second set should be made with no paper on the platen and the cover down. The third set should be taken with no paper on the platen and the cover up. The last set should be a copy of any original document, which covers at least a quarter of the page. A full color original should be used when taking samples of a full color copier. These samples should be submitted to the lab with the questioned documents.

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