The effects of nano-fibrillated cellulose as a coating agent for screen printing, 2012 Advanced Coating Fundamentals Symposium

Please Note: This document will be available in PDF format in the "My Electronic Documents" link on the home page once your order has been completed. Please make sure you have the latest version of Acrobat Reader. Click on the Acrobat Reader icon to check for the latest version, it’s FREE. To print a hardcopy of a PDF file correctly you must have a postscript printer. If you are not sure if your printer is a postscript printer please refer to your owner’s manual.

Purchase of electronic (downloadable) documents made at www.tappi.org by credit cards, followed by instant download CANNOT be cancelled. We do not offer refunds on electronic download documents.

This paper reports on the printability characteristics achieved with a method involving screen printing on paper coated with nano-fibrillated cellulose (NFC). In the study, ink pigment deposition and vehicle penetration were elucidated using a scanning electron microscope (SEM) with a focused ion beam system (FIB) and a confocal laser scanning microscope (CLSM), and two types of inks (the penetration-type and the non-penetration-type) were compared.

The SEM images obtained showed that most pigment in penetration-type ink was deposited on the surface and that vehicles penetrated the sheets. Plate-shaped pearl luster pigments were oriented in the ink layer, which led to better color shifting properties and other optical variation effects. Although penetration-type ink offers superior properties of optical variation, it is also characterized by problems with strike-through, durability and other considerations due to excessive vehicle penetration with especially porous and highly absorbent sheets. However, these problems can be solved by applying NFC to control vehicle penetration rates. CLSM images clearly showed that NFC coating prevents vehicles from penetrating and spreading excessively into the substrate. The results in this report suggest that NFC can capture not only small particles of ink pigment but also even liquids such as ink vehicles. Accordingly, NFC is seen as a promising environmentally friendly surface treatment for use with low-viscosity inks for screen printing because it can capture vehicles near the surface and prevent them from penetrating the sheet excessively.