Moisture Absorption
Moisture absorption ratios in dry flax fibers compared to their bone-dry mass under specified humidity conditions determine the physical properties and processing behavior of the textile. This variable, called flax moisture regain, directly affects fiber flexibility and the ease with which it can be drafted and spun into yarn. Because flax is highly hygroscopic, its moisture content fluctuates rapidly with the surrounding environment.
Spinning mills must monitor this property to maintain consistent processing conditions on the production floor.
Standard Atmosphere
Industrial testing requires that the flax be conditioned in a standardized environment of twenty degrees Celsius and sixty-five percent relative humidity until it reaches equilibrium. Under these conditions, the natural regain of flax stabilizes at a standard percentage, which is higher than that of cotton or synthetic fibers. This moisture makes the fibers more pliable, reducing static electricity and fiber breakage during high-speed spinning operations.
In dry spinning mills, humidifier systems maintain this moisture level to prevent the flax from becoming brittle and generating excessive dust. By controlling the moisture regain, mills can optimize the draft and yarn consistency, ensuring that the spun yarn has the necessary strength for high-speed loom operations.
Commercial Weight
Trade transactions use the standard regain value to calculate the billable weight of fiber shipments, ensuring that buyers do not pay for excess water. When a shipment arrives with moisture above the standard limit, the invoice weight is adjusted downward to reflect the true dry fiber mass. This practice protects the buyer from paying fiber prices for water weight gained during transit or storage.
The commercial calculation prevents disputes between spinning mills and fiber merchants.
