ON-LINE HYDROENHANCEMENT EVALUATION TECHNIQUE

A technique and apparatus for evaluating the degree of hydroenhancement achieved in a woven fabric. The degree of hydroenhancement is related to the permeability of the woven fabric (i.e., t he permeability of the woven fabric will decrease as the hydroenhancement increases). The hydroenhanced fabric is pulled over a vacuum source (while a constant vacuum is maintained) and the air flow through the fabric is measured. The air flow per unit area of fabric is then calculated and define d as the permeability. Alternatively, the permeability can be calculated by maintaining a constant air flow and measuring the vacuum drop associated wit h the treated fabric. The degree of hydroenhancement may then be assessed as related to this permeability measurement. The measurement may be performed on "wet" fabric immediately after it exits the hydroenhancement process and the permeability measurements used as a control signal for the hydroenhancement process (that is, to regulate the machinery used to impart the hydroenhanced quality to the fabric). Alternatively, the measurement may be performed on "dry" fabric and used, as an audit process, to assess the quality of the finished product.