Chemical Agent
Synthetic polymers and natural carbohydrates create a protective film during the warp preparation phase of linen manufacturing. This pva starch size formulation coats flax yarns to reduce abrasion and friction during the mechanical stresses of high speed loom operation. The coating adheres to the fibre surface and provides sufficient tensile strength for the warp sheets to move through the reed and heddles without breakage.
Moisture absorption and shedding characteristics determine the operational limit of the chemical protection.
Application Protocol
Mills prepare the mixture by blending polyvinyl alcohol with modified starch in heated aqueous solutions to ensure complete solubility. Workers control the concentration levels based on the specific fibre grade and yarn count to maintain the required sizing percentage on the warp beam. Sensors measure the viscosity and temperature of the mixture to maintain consistency across the entire supply batch.
Proper viscosity ensures the size penetrates the core of the yarn, which prevents surface cracking during the drying process on the cylinders. Drying efficiency dictates the speed of the sizing machine, as incomplete moisture removal results in tacky yarns that stick to loom components.
Quality Verification
Inspection of the warp quality occurs through standardized shedding tests that evaluate how much dust forms when the yarn contacts a rotating cylinder. Laboratory technicians weigh samples before and after desizing to calculate the dry add on percentage required for buyer specifications. Mill standards for sizing retention vary from the acceptance criteria established by the garment manufacturer or the final fabric brand.
Uniformity in the coating thickness determines the performance of the fabric finish, as inconsistent application creates uneven dye uptake in subsequent production stages. The degree of film continuity provides a reliable metric for predicting how the warp will perform under the tension of industrial weaving machines.
