ASTM D4361-97

Designation: D 4361 – 97
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Test Method for
Apparent Tack of Printing Inks and Vehicles by a Three-
1
Roller Tackmeter
This standard is issued under the fixed designation D 4361; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 2.1.3.1 Discussion—Flying is generally most severe during
rapid roller acceleration such as occurs when switching imme-
1.1 This test method covers the procedure for determining
diately from zero or a slow speed to a high operating speed.
the apparent tack of printing inks using a mechanical or
2.1.4 misting—the tendency of a printing ink or vehicle to
electronic model of a three-roller tackmeter.
be ejected as a fine aerosol from a roller distribution system.
1.2 This test method is applicable to paste-type printing inks
2.1.4.1 Discussion—Misting is generally most severe at
and vehicles that are essentially nonvolatile under ordinary
high operating speeds and with fluids that produce long
room conditions.
filaments.
1.3 The values stated in inch-pound units are to be regarded
as the standard. The values given in parentheses are for
3. Summary of Test Method
information only.
3.1 A thin film of the test printing ink or vehicle is applied
1.4 This standard does not purport to address all of the
to the three-roller distribution system of the tackmeter, which
safety concerns, if any, associated with its use. It is the
operates at speeds comparable to those on production printing
responsibility of the user of this standard to establish appro-
presses. Measurement of the frictional torque induced by drag
priate safety and health practices and determine the applica-
forces in the splitting film provides an arbitrary value for
bility of regulatory limitations prior to use.
apparent tack. On mechanical models, the torque is determined
2. Terminology with a manually balanced lever arm, a direct-reading attach-
ment, or a recorder; on electronic models, with a digital
2.1 Definitions of Terms Specific to This Standard:
readout, recorder, or printer. Readings are in units of gram-
2.1.1 tack—a function of the force required to split a thin
meters (g-m).
fluid film of a printing ink or vehicle between two rapidly
3.2 The procedure in this test method is designed to give a
separating surfaces; it is a rheological parameter indicative of
single value for apparent tack at a specific set of instrument
internal cohesion of the fluid.
conditions. Typical conditions are as follows: a cooling water
2.1.1.1 Discussion—Tack of a printing ink or vehicle is not
temperature of 90°F (32.2°C); a volume of 1.32 mL (film
a fixed number but varies with operating conditions, primarily
thickness 12.3 μm) of the test printing ink or vehicle applied to
separation velocity, splitting area, and film thickness. Tack also
the rollers; an operating speed of 400 r/min for vehicles, 800
varies with changes in the rheological properties of the ink or
r/min for sheet-fed offset inks, and 1200 r/min for web-fed
vehicle due to time, temperature, and interactions with the
inks; and a reading after 1 min of operation. Alternative
separating surfaces. In practice, one or more of these surfaces
conditions may be used by agreement between the supplier and
usually consist of rubber-like rollers that differ in composition
the customer.
and geometry and whose properties tend to change with age,
3.3 Instructions are also given for calibration of the Inko-
nature of previously run fluids, type of wash-up solvent, and
meter and for minimizing effects of interactions among the
mechanical flaws. On laboratory instruments, tack readings are
rollers, test fluids, and wash-up solvents.
also sensitive to the calibration and zero accuracy of the
tackmeter employed.
4. Significance and Use
2.1.2 apparent tack—a tack reading obtained at a specific
4.1 Tack of printing inks controls their high-speed transfer
set of conditions.
properties, as manifested by throughput in roll milling, picking
2.1.3 flying—the tendency of a printing ink or vehicle to be
of paper during printing, and wet trapping in multicolor
ejected as large globules from a roller distribution system.
printing. Although an apparent tack measurement does not
completely predict the transfer performance of an ink or a
1
This test method is under the jurisdiction of ASTM Committee D-1 on Paint
vehicle, it provides a meaningful parameter for quality control,
and Related Coatings, Materials, and Applications and is the direct responsibility of
development, and research.
Subcommittee D01.56 on Printing Inks. Subcommittee D01.37 on Ink Vehicles
assisted in the development of the vehicle porti
...