Date of Award

6-1997

Degree Name

Master of Science

Department

Paper Engineering, Chemical Engineering and Imaging

First Advisor

Dr. Brian Scheller

Second Advisor

Dr. Raja Aravamuthan

Third Advisor

Dr. Ellsworth Shriver

Access Setting

Masters Thesis-Open Access

Abstract

The behavior of coatings and their study is becoming more important in proportion to additional use of coated paper. Good coating is key to enhance print quality. Blade coating is quite common, but rod coating is coming back for the advantages it has over blade coating. The process of rod coating is simpler and maintenance is easier. Coatings at low solids can be applied with ease and the impurities are washed away by rod rotation. The surface profile of coating is a potential concern, due to streaks in the machine direction. If the coating is immobilized before the streaks heal, these streaks become coating defects. These defects are often referred to as 'rod streaks' and are partly caused by the interaction of wire and hydrodynamic forces.

Wire-wound rods were developed to apply coatings more uniformly than it was done with smooth rods. The problem of streaks still exists. A ribbing pattern also develops. There are several factors that cause these problems. The coating solids and speed play an important role in this process. This study was done to see the effects of speed and coating solids on surface formation in terms of peaks and valleys generated at three different speeds and solids levels. The ribbing effect was also analyzed.

Share

COinS