Abstract
By means of dynamic water retention tests using a bench blade coater, swelling behavior of fibrous base sheet on coating smoothness was observed in the blade coating process and the mechanism of coating layer formation was studied. This paper describes the results obtained from the experiments.1) This dynamic water retention test method has several advantages such as simple operation, superior reproducibility and real time information.2) There was a sufficient correlation between volume of water transported from coating in to base sheet and roughness of coated paper. Also there is a tendency that when volume of water transported in to base sheet gets smaller, coated surface becomes smoother.3) There was a significant correlation between sheet gloss and dwell time from application to blade metering as well as volume of absorbed water. The formation process of coating layer was strongly influenced by dewatering behavior of coating color.4) There indicate that relations between formation of so-called filter cakes of coating color and dwell time are very important. As primary factors, water retention of color, initial color solids, immobilized point and base sheet properties for coating such as porosity or sizing can be mentioned.5) Double coating is highly effective as a means of getting superior coating smoothness. This is because water absorbency into base sheet can be minimized by dividing coating weight into under and top coatings.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
