Modelling of the Motion and Interaction of a Droplet of an Inkjet Printing Process with Physically Treated Polymers Substrates

Abstract

This study examines the effect of energetic surface treatment on the adhesion strength of high-density polyethylene (HDPE), polypropylene (PP) and polyethylene terephthalate (PET) substrates. The purpose of this work is to determine the surface wettability of polymers suitable for food contact. These plastics have been treated with various pre-treatment methods to improve surface tension and good adhesion for inkjet printing and avoid any visual changes. It is important to determine the adhesion of the ink to the polymer surface to improve post-consumer recycling. Digital inks have been tested on various treated plastics to analyse coating properties and adhesion forces in accordance with DIN ISO 2409 standards. The impact of the inkjet droplet on the treated and non-treated surface was also investigated using the COMSOL computer simulation software.

Plasma Treatment of Large-Area Polymer Substrates for the Enhanced Adhesion of UV–Digital Printing

“…The change in SFE of the treated surface affects the ink droplet shape and its diameter, which can develop in time. This effect is more pronounced for LTP-treated substrates [ 18 ]. Moreover, these authors observed that the UV–ink could undergo considerable degradation of its adhesion after 24 h on untreated and cleaned surfaces compared to stable ink adhesion to LTP-treated surfaces.…”

“…In this study, the DCSBD plasma modified the surface of polymethylmethacrylate (PMMA) and polycarbonate (PC) substrates, often considered glass substitutes in UV–digital printing. The end-user of UV–digital printers requires a substantial increase in the adhesion and standardization of the printed layer quality on polymer substrates from different manufacturers [ 18 ]. Thus, process variables (plasma reactor configuration, treatment time, and treatment distance) were identified and used for experimental tests.…”

“…The stability of such printing depends on the choice of substrate materials and the printed color pattern. Commonly used polymeric materials have a smooth surface and low surface energy, which often (but not inevitably) causes an insufficient adhesion of inks used for UV-digital printing [15][16][17][18]. The adhesion of the printed color pattern, or its abrasion resistance, then affects the final product's usage and positioning, or the printed substrate's impact, depending on climatic conditions (e.g., outdoor conditions, humidity, and temperature).…”

Plasma Treatment of the Large-Area Polymer Substrates for the Enhanced Adhesion of UV-Digital Printing

“…The stability of such printing depends on the choice of substrate materials and the printed color pattern. Commonly used polymeric materials have a smooth surface and low surface energy, which often (but not inevitably) causes an insufficient adhesion of inks used for UV-digital printing [15][16][17][18]. The adhesion of the printed color pattern, or its abrasion resistance, then affects the final product's usage and positioning, or the printed substrate's impact, depending on climatic conditions (e.g., outdoor conditions, humidity, and temperature).…”

Splitting an Impacting Droplet by a Superhydrophobic Wire

“…Single droplet splitting is vital for the highly efficient clinical detection [24], precious inkjet printing [25], open-air microfluidic devices [26], and interfacial heat transfer [27], whereas finding an efficient and quick method of separating a drop with little assistance from tools is still challenging. Recently, superhydrophobic surfaces have been shown to be a resourceful way to control wettability and manipulation of droplet motions.…”