The objective of this thesis is to study a recurrent printing defect when industrial printing of PVC flooring, the marbling. This defect appears randomly in the printing production line with variable levels. It appears like a textured print instead of normally uniform solid print which generates many nonconformities of the products. The purpose of this work is to understand the origin of the phenomenon of marbling in order to identify the cause(s).
To achieve this objective, it was necessary to develop a reliable and non-subjective tool to quantify the defect based on an image analysis technic. This was used to study the main parameters that may be the cause of the marbling: the substrate wettability, the printing process parameters as well as the inks properties (surface tension, rheology). All of this work has highlighted the role of the formulated inks flow threshold, the phenomenon being linked to instabilities like Saffman-Taylor type raising in the cleavage of the ink film during the printing step of the flooring.