Standard Moisture Regain Determination in Scutched Flax Fibre
Standard moisture regain in scutched flax fibre is set at 12.0% of bone-dry mass using ISO 6741-1 forced-convection oven drying at 105 degrees Celsius.
Equilibrium Relative Humidity
Moisture State
An atmospheric condition represents the state where a textile material neither gains nor loses moisture to the surrounding air. In flax fiber processing, the equilibrium relative humidity of the storage environment determines the moisture regain of the raw material before spinning. This balance point varies depending on whether the fiber is approaching the state from a dry or a wet condition.
Industrial Control
Spinning mills maintain controlled environments to ensure the flax remains pliable during drawing and drafting. When the ambient humidity matches the moisture equilibrium of the fibers, the material behaves consistently on the machines, reducing the frequency of yarn breakages. Sensors in the processing rooms monitor the air continuously to adjust humidification systems.
This control prevents both the excessive dryness that causes brittleness and the high moisture that encourages mold growth. The target levels are set according to the specific fiber grade and the mechanical demands of the spinning frames.
Fiber Performance
The mechanical strength of linen fibers increases when they contain optimal amounts of bound water. Achieving the correct equilibrium relative humidity ensures that the fiber undergoes drafting without excessive friction or static electricity. Consequently, this state is critical for maintaining uniform yarn count across different production batches.