Water Retention & DWR
Water retention (WR) plays a very important role in the quality of coated papers. The first time in the history, it’s possible to really simulate the static and the dynamic processes of coating machines as well as to measure the very important influence of base papers on the WR.
With this new analyzer it is possible to measure characteristics of the coating colour as well as the influence of the base paper on water retention. Automated dynamic and static phases simulate the real circumstances of a coating machine the total measurement time being only about three minutes.
The base paper is weighed and then the paper sample is placed together with the filter on the lid of the DWR.
The lid is closed. In order to simulate application the pressure (1 – 2 bar) and time (s) is chosen from PC as well as the static time in order to simulate the time between an applicator and a blade.
The coating color flows under pressure when the applicator and the coater are simulated.
The flow and the pressure are important factors when one is simulating the real conditions.
The instrument makes the measurement automatically. After the measurement the lid is opened and the base paper is weighed.