Moisture in paper plays an important role in the printing and converting process, as it can vary from 1-12% depending on the relative humidity and type of pulp and chemicals used. It is essential to control the moisture content of paper and keep it stable during the converting process, as poor moisture control can have a negative effect resulting in curl, poor stability and out-of-specification product.

Measuring coat weights is also important factor during paper converting for the precise control of films, water based adhesives, resins and hot-melt glue applications. Polyethylene, polypropylene and other coatings, such as PVC, can also be measured and controlled to a high degree of accuracy.

MoistTech has developed technology with the latest electronics and low wavelength technology to provide a remedy to these concerns. the IR3000 sensor was developed specifically for the measurement for online installation and to withstand a variety of process conditions regarding temperature and pressure. Thus, the IR3000 provides users with high accuracy and measurement speed that is up to 20 times faster than conventional NIR instruments, the company says.  With the pre-calibration of the IR3000, users install and commission their sensor within minutes.

The IR3000 helps control the re-moisturizing process, monitor any additions of adhesive coatings and detect coating defects. MoistTech’s IR3000 sensor is installed where 100% inspection is required and quality needs to be maintained to very high standards. “Our sensor calibrations, measurement wavelengths, algorithms and sensor optical requirements are pre-set at the factory,” the company states. “Typical paper moisture accuracy is ±0.05%, coating accuracy varies from 0.1 to 0.01 micron depending on coating type. Typical analog range is 0-10% moisture and up to as much as 80%, subject to application. The outputs can be adjusted to optimize PLC or recording requirements.”
 
MoistTech has seen positive customer feedback in this arena, too. Recently, a customer was having issues with controlling the moisture on different types of paperboard. Before the MoistTech IR-3000 Online Moisture Sensor was installed, the only method of measurement was by grabbing a sample and taking it to the lab. Their lab method consists on weighting the sample, drying at a low temperature for a certain amount of time and then weighting it again, based on the lost weight they calculate the amount of moisture of the product. Unfortunately, this method takes a lot of time and if the product is running out of the moisture range needed then by the time they figure out the moisture content is too late and this represent loss of energy and product that needs to be reclaimed.

“By installing the MoistTech IR-3000 Online Moisture sensor over the process, our customer could now monitor the moisture continuously at a +/- 0.1% accuracy which helped tremendously with being able to make any adjustments on the speed or the temperature of their dryers,” says MoistTech. “The sensor was also integrated with their PLC using one of our three 4-20mA outputs.  Not only can the IR-3000 measure moisture but also our customer applies a water-based coating to some of their product and our sensor can measure the thickness of the coating at a very successful accuracy. Installing the IR-3000 Online Sensor will help our customer act immediately on any issues that might arise during production.”