5.1 Actual direct measurements of apparent viscosity and stress at shear rates of interest can be useful in the practical control of ink viscosity during production and the specification acceptance between supplier and purchaser.

5.2 Use of the Duke automated viscometer provides direct measurements for viscosity and yield value versus extrapolating data points that may be far from the desired shear rates.

1.1 This test method covers the procedure for determining the viscosity of varnishes, ink vehicles, and similar liquids that are essentially nonvolatile and unreactive under ordinary room conditions using the Duke Automated high-shear rod and collar viscometer.2

1.2 The instrument in this test method is similar in principle to the falling-rod viscometer described in Test Method D4040 except that the collar is motor driven and the range of available shear stresses is considerably greater. This instrument is capable of measured and extrapolated viscosity and yield values provided the proper model is chosen for the given application. See Section 6 for the ranges of specified models.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

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