Material Chemistry
Flax fibres contain natural non-cellulosic polymers that influence how the yarn behaves when exposed to moisture or liquid dyes. Within the raw cell wall, hemicellulose sorption determines the rate and capacity of water uptake during the wet spinning and finishing stages. This natural chemical trait distinguishes bast fibres from pure cotton, which contains fewer non-cellulosic elements.
Moisture Mechanism
High humidity conditions cause the amorphous sections of the fibre cell wall to expand as they draw in water molecules. This hemicellulose sorption process affects the swelling of the yarn during wet spinning on the ring frames. If the spinning water temperature is too low, these polymers do not soften, which limits the flexibility of the yarn.
Control of this water absorption is necessary to keep the yarn strength uniform. If the fibre absorbs too much water, the yarn dries too slowly, which can lead to mildew in storage.
Finishing Behavior
Dyeing technicians adjust their chemical formulas based on how much the non-cellulosic polymers absorb the colorants. The mill lab measures this swelling behaviour to adjust the washing baths. Balanced absorption prevents uneven dye spots in the finished fabric.
This control gives the exported linen its uniform color.
