Metallic inks are in widespread use in the graphic arts industry, but there currentiy is no way to "put a number" on metallic gloss. Process-control methods, such as densitometry, which analyzes how light is absorbed into the ink layer, are not usable for metallics, since hardly any light gets absorbed. In addition, it is very difficult to see visual differences when the ink film thickness crosses a certain threshold.
Dr. Jonathan Arney at the Chester F. Carlson Center for Imaging Science at Rochester Institute of Technology (RTT) has been using a micro-goniophotometer for analyzing paper gloss on a microstructure level, and in this exploratory research, the device was used to analyze metallic prints. Two sets of measurements were made to determine the device's tolerance and range. In the first experiment, two very different samples visually were measured to determine if the device can detect the difference. The second experiment consisted of measuring two visually similar samples to determine if the device can detect this small visual difference.
The results showed that the device can detect the large visual difference in the first experiment, the difference was observable in the gloss images, as well as in the numerical data. In the second experiment, a small difference was detected; however, without repeated measurements, there was no way to rule out the difference being caused by experimental factors and noise. Overall, the results showed that the micro-gomophotometer can be used to analyze metallics; the results also indicated that further study in this area is justified.
Library of Congress Subject Headings
Paper--Printing properties--Testing; Paper coatings; Paper finishing; Metallic oxides
Department, Program, or Center
School of Print Media (CIAS)
Suni, Saara, "Analyzing Metallic Gloss Using a Micro-Goniophotometer" (2007). Thesis. Rochester Institute of Technology. Accessed from
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