Study of the lightfastness properties of prints on blister foils by spectral reflectance

Abstract

This study describes the lightfastness properties of printed foil samples due to long-time exposure. Lightfastness is an important property for any kind of print products to assess their print stability. The fastness properties of prints can be described in terms of print durability and image stability. It may also be used for verification of printed expiry date and authenticity or validity of the product. Moreover, any kind of deterioration in package print quality will affect the product's sale adversely. Little work has been conducted to study the fastness properties of printed films and foils. In this work, blister foils printed in the gravure printing process have been taken as the sample as they have extensive usage in food and medicine packaging. An artificial lightfastness tester BGD 865/A Bench Xenon Test Chamber (B-SUN) is used to study the light fastness of Cyan, Magenta, Yellow, and Black inks on the foil. The spectral curves and colorimetric values are measured using an Ocean Optics Spectroradiometer (DH2000BAL) before and after exposure. A kinetic model is proposed to predict the fading rate of the printed foil. The optimal model has given excellent prediction with a correlation coefficient of 0.90 to 0.93 for Cyan, Magenta, Yellow, and Black prints, respectively. The largest color difference ΔE 00 is achieved for Yellow print followed by Magenta. Cyan and Black prints have shown small changes with time when the gravure prints are exposed to the artificial aging chamber. K E Y W O R D S

Artificial neural network approach to predict the lightfastness of gravure prints on the plastic film

“…In earlier work, a kinetic model was used to describe fading characteristics of prints on the metal foil substrate where it worked well with correlation coefficients ranged between 0.90 and 0.93 for Cyan, Magenta, Yellow, and Black prints. 1 Hence, it can be stated that the kinetic model performed well for the metal foil. In the present study, similar experiments were done on plastic films and it was observed that the correlation coefficient (R 2 ) for the regression model of Cyan, Magenta, Yellow, and Black prints is 0.76, 0.98, 0.14, and 0.45 respectively.…”

“…To examine the effect of the lightfastness properties of prints, sets of test print samples are prepared as described in the Experimental section of our previous study. 1 The printing unit consists of electronically engraved four-color printing cylinders, blower, and heater. The prints are allowed to dry at 50 C to 60 C temperature.…”

“…In our previous studies, the kinetic model is applied to estimate the fading behavior of prints on the foil with time. 1 The current study is the complement of our previous study and in this study, an ANN model has been developed for prediction of the fading behavior of prints on film to compare the results.…”

“…42 A similar lightfastness procedure has been carried out on the film prints, which is mentioned in the previous study. 1 This study has used the xenon test chamber for conducting the lightfastness test of film prints. In this lightfastness tester, the irradiance level is set to 0.35 W/m 2 .…”

“…The previous article has shown the lightfastness properties of prints on the foil substrate, which is mostly used by the food and pharmaceutical packaging industry due to its inertness property. 1 This article has focused on the fading analysis of plastic film considering the extensive application in the food and other packaging industries. The film is chosen as food-grade plastic depending on its wide range of properties that customers exactly require.…”