Performance Evaluation of Gravimetric Absorbancy Tester (GAT), 1996 Nonwovens Conference Proceedings

Kambiz B. Makoui--Absorbency is one of the key fundamental properties of the consumer paper product. Test methods such as Drop Test, Basket Sink Test (BS), Rapid Absorbency Test (RAT) originally developed by the TRI of Princeton, NJ, and the Gravimetric Absorbency Testing unit (GAT) are some of the tools used by various industries to measure the absorption properties of an absorbent web. Air Products uses a state-of-the- art custom designed absorbency (GAT) unit to provide new ways to measure absorbency of nonwovens accurately and efficiently. This custom designed, automated gravimetric absorbency unit was primarily developed to study the liquid uptake by the absorbent product in a direction perpendicular to the plane of a fabric as well as in-plane absorption. Using “GAT” one can measure the absorption rate as well as total capacity of a web from the first moment of liquid-substrate contact until a steady state is reached. Customization of the “GAT” allows us to measure other functional properties of an absorbency core such as liquid retention under load, resiliency, and wet bulk. The resiliency and wet bulk of a fabric are important properties to measure, since they describe the ability of a product to distribute liquid to different areas of the fabric. These properties are indicative of how well an emulsion binder can penetrate into an airlaid web. The interaction between the pulp and binder is one of the key properties we can study using the unit. Other test methods and devices mentioned above do not have the capability or accuracy of the GAT unit. The differences between each of the other test method and their absorption results are discussed.