1. This test
method measures the contact angle of a test liquid in contact with a flat
specimen of a film or a paper substrate under specified test conditions. This
test method may be used with any liquid of interest which is compatible with
the equipment used, particularly with regard to liquid viscosity, tackiness,
and vapor pressure (evaporation). This test method may be used with any
substrate of interest, which can be cut to dimensions compatible with the
equipment used.
2. For
materials which sorb the test liquid under the specified test conditions, the
rate of change of the contact angle as a function of time may be significant,
and may be determined using procedures described in this test method. It is
also possible to evaluate the sorptive properties of a surface, as the remaining liquid volume on top of the specimen surface is measured as a function of time.
3. The
conditions required in this test method specify reagent water as the test
liquid when testing papers designed to be absorbent, such as absorbent tissue
grades.
4. Conditions
are specified for the testing of a wide range of papers considered to be of low
absorbance or nonabsorbent, including release papers, sized, coated, or unsized
papers designed for printing, writing, wrapping, and similar tasks where the
paper surface interaction with aqueous or solvent based inks or other aqueous
or nonaqueous liquids is important. In such cases, test liquids other than
reagent water, including writing and printing inks, or organic liquids or mixtures
of organic liquids may be used as the test liquid upon prior agreement of those
involved in the testing, provided the liquid is compatible with the equipment
used. Where test liquids other than reagent water are used, the actual liquid
used is reported.
5. Conditions
are also specified for the testing of polymer films, polymer-coated papers,
paper laminates, felt, textiles and non-wovens, using water or other fluids
compatible with the equipment and important to the end-use applications of the materials
tested, including gluing and printing.
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.
