1.1 This test method determines the liquid sorption of bibulous paper, paperboard, and paper products using gravimetric principles.

1.1.1 The procedure in this test method describes testing of absorbent materials such as those in 1.1. Similar testing may be done on composite absorbent products, incorporating cellulose and nonwoven fabrics, polymer films, or other similar materials for use such as absorbent pads, wipes, and so on with slight modification. This test method does not describe the application of this technique to textiles.

1.2 The standard test liquid is distilled water.

1.2.1 Other test liquids of interest may be used if desired, provided they are compatible with the liquid delivery system specified.

1.2.1.1 Examples of such test liquids include, but are not limited to, buffered solutions of distilled water, fruit or vegetable juices, milk, synthetic body liquids such as urine, and organic fluids such as salad oil, cooking oil, motor oil, and others.

1.3 The test liquid is delivered at an effective negative head pressure after initiating liquid flow (wicking). This allows the controlling sorptive properties to be demand wettability, the ability of the specimen to absorb through capillarity and surface wetting.

1.3.1 Using the equipment and principles described, absorption at other instrument configurations and head pressures, as well as desorption may be measured.

1.4 This test method measures both the rate and capacity of liquid sorption through demand wettability or wicking. Liquid capacity is defined as the point in the analysis where the sorption rate falls below 3.0 mg in 5 s. Agreed intermediate points are measured during the analysis to determine rate.

1.5 An analog or digital report of the sorptive behavior of the test specimen may be produced, if desired, to further characterize its sorptive behavior.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.