Investigation of Migration Model of Printing Inks on Paper Packaging

The printed packaging was divided into ink layer and paper layer. The migration model was developed based on penetration and Fick's second law. hm and KF,P at the interface of the paper and the food were considered in the model. After the penetration of the ink, the distribution of the contaminant in the paper layer was discrepant for paper with different thickness. The model could be simplified to be single-layer or two-layer packaging model in special cases. Three special cases of the model were validated: (1) special case 1 of the model was a single-layer model just considering hm at the interface. This special model was compared with the classical model; (2) special case 2 of the model was also a single-layer model validated by experimental data in reference; and (3) special case 3 was the two-layer model validated by experimental data in reference. The model was proven to be effective by above validation. Practical Applications The use of migration models to evaluate the safety of plastic food packaging is economical and time-saving compared with the experiments. As the second important packaging material, paper packaging is widely used for its environmental friendliness. However, up until now, there is no general migration model of paper packaging. A migration model of the contaminants from the inks on paper packaging was developed to predict them in different packaged food under certain migration conditions. Diffusion, partition and mass transfer coefficients were introduced to the model for better prediction. The simplified model can be used for other packaging materials and single or multilayer packaging. This model can help to design packages with acceptable migration of the contaminants.