Waterborne Barrier Dispersion Application Parameters on Folding Boxboard
Waterborne dispersion application on folding boxboard requires precise coat weight control, shear-matched viscosity, and staged drying to prevent pinholing.
Repulpability ISO 187
Environmental Standard
The environmental standard for temperature and humidity used to condition paper samples provides a baseline for evaluating mechanical performance. While the code refers to the atmosphere, repulpability iso 187 requirements ensure that the moisture content of the sample is uniform before it enters the pulping process. Consistency is achieved because the strength of the hydrogen bonds between fibres changes with the amount of absorbed water.
Laboratory Procedure
Samples are stored in a controlled room at twenty-three degrees Celsius and fifty percent relative humidity for a minimum period of four hours. Applying the repulpability iso 187 standard prevents variations in ambient weather from skewing the results of the disintegration test. Standardized conditions allow different laboratories to compare the ease with which a coated paper breaks down into individual fibres.
If the paper is too dry, it may resist initial wetting and lead to an inaccurate assessment of the total yield.
Testing Boundary
Achieving this equilibrium is the first step in a larger protocol that measures the amount of screen rejects produced during recycling. The repulpability iso 187 conditioning does not account for the chemical additives used in the pulper, which also affect the separation of fibres from coatings. It simply provides the physical starting point that makes the rest of the data defensible.