Dirt Control in DIP Process

—Recent Trend of Dirt and On-line Dirt Measurements—

Abstract

In DIP process, the troubles of dirt such as stickies and residual inks are currently increasing at rapidly pace because of downgrading of recycled paper and improvement of printing technique. Technical advance of screen and dispersion system is able to achieve more selective removal of dirt ; however, it is hard to solve the issue of dirt completely. We need knowledge of dirt and instrument to control it so that we are annoyed with dirt troubles.
On-line dirt counter enables constant surveillance of dirt and prompt attention without lag lime by measuring it directly in the pulp slurry on the process. We are taking full advantage of dirt management since we had phased in it to three DIP processes.
In this paper we present recent trends of dirt and examples of dirt measurements by using on-line dirt counter.