Standard Test Method for Apparent Tack of Printing Inks and Vehicles by a Three-Roller Tackmeter

SIGNIFICANCE AND USE
Tack of printing inks controls their high-speed transfer properties, as manifested by throughput in roll milling, picking of paper during printing, and wet trapping in multicolor printing. Although an apparent tack measurement does not completely predict the transfer performance of an ink or a vehicle, it provides a meaningful parameter for quality control, development, and research.
A given tackmeter will produce repeatable results on a day-to-day basis only if proper attention is paid to calibration and maintenance procedures and to control of experimental variables referred to in 2.1.1.1.
Two or more instruments may not produce identical apparent tack readings, but if each gives repeatable results, they may be mathematically correlated.
Note 1—A number of three-roller tackmeters are available which differ in design features such as roller weight, geometry, and composition of the distribution system. It cannot be presumed that test results from these other types of tackmeters will either agree or correlate with those from the tackmeters specified in 6.1 and 6.2 of this test method.
SCOPE
1.1 This test method covers the procedure for determining the apparent tack of printing inks using a mechanical or electronic model of a three-roller tackmeter.
1.2 This test method is applicable to paste-type printing inks and vehicles that are essentially nonvolatile under ordinary room conditions.
1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.
1.4  This standard does not purport to address all of the safety problems 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.

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ASTM D4361-97(2002) - Standard Test Method for Apparent Tack of Printing Inks and Vehicles by a Three-Roller Tackmeter
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D4361–97(Reapproved2002)
Standard Test Method for
Apparent Tack of Printing Inks and Vehicles by a Three-
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 flying, n—the tendency of a printing ink or vehicle to
be ejected as large globules from a roller distribution system.
1.1 This test method covers the procedure for determining
2.1.3.1 Discussion—Flying is generally most severe during
the apparent tack of printing inks using a mechanical or
rapid roller acceleration such as occurs when switching imme-
electronic model of a three-roller tackmeter.
diately from zero or a slow speed to a high operating speed.
1.2 Thistestmethodisapplicabletopaste-typeprintinginks
2.1.4 misting, n—thetendencyofaprintinginkorvehicleto
and vehicles that are essentially nonvolatile under ordinary
be ejected as a fine aerosol from a roller distribution system.
room conditions.
2.1.4.1 Discussion—Misting is generally most severe at
1.3 The values stated in inch-pound units are to be regarded
high operating speeds and with fluids that produce long
as the standard. The values given in parentheses are for
filaments.
information only.
1.4 This standard does not purport to address all of the
3. Summary of Test Method
safety concerns, if any, associated with its use. It is the
3.1 A thin film of the test printing ink or vehicle is applied
responsibility of the user of this standard to establish appro-
to the three-roller distribution system of the tackmeter, which
priate safety and health practices and determine the applica-
operates at speeds comparable to those on production printing
bility of regulatory limitations prior to use.
presses. Measurement of the frictional torque induced by drag
2. Terminology forces in the splitting film provides an arbitrary value for
apparent tack. On mechanical models, the torque is determined
2.1 Definitions of Terms Specific to This Standard:
with a manually balanced lever arm, a direct-reading attach-
2.1.1 tack, n—a function of the force required to split a thin
ment, or a recorder; on electronic models, with a digital
fluid film of a printing ink or vehicle between two rapidly
readout, recorder, or printer. Readings are in units of gram-
separating surfaces; it is a rheological parameter indicative of
meters (g-m).
internal cohesion of the fluid.
3.2 The procedure in this test method is designed to give a
2.1.1.1 Discussion—Tack of a printing ink or vehicle is not
single value for apparent tack at a specific set of instrument
a fixed number but varies with operating conditions, primarily
conditions. Typical conditions are as follows: a cooling water
separation velocity, splitting area, and film thickness.Tack also
temperature of 90°F (32.2°C); a volume of 1.32 mL (film
varies with changes in the rheological properties of the ink or
thickness 12.3 µm) of the test printing ink or vehicle applied to
vehicle due to time, temperature, and interactions with the
the rollers; an operating speed of 400 r/min for vehicles, 800
separating surfaces. In practice, one or more of these surfaces
r/min for sheet-fed offset inks, and 1200 r/min for web-fed
usually consist of rubber-like rollers that differ in composition
inks; and a reading after 1 min of operation. Alternative
and geometry and whose properties tend to change with age,
conditions may be used by agreement between the supplier and
nature of previously run fluids, type of wash-up solvent, and
the customer.
mechanical flaws. On laboratory instruments, tack readings are
3.3 Instructions are also given for calibration of the Inko-
also sensitive to the calibration and zero accuracy of the
meter and for minimizing effects of interactions among the
tackmeter employed.
rollers, test fluids, and wash-up solvents.
2.1.2 apparent tack, n—a tack reading obtained at a specific
set of conditions.
4. Significance and Use
4.1 Tack of printing inks controls their high-speed transfer
This test method is under the jurisdiction of ASTM Committee D01 on Paint
properties, as manifested by throughput in roll milling, picking
and Related Coatings, Materials, andApplications and is the direct responsibility of
of paper during printing, and wet trapping in multicolor
Subcommittee D01.56 on Printing Inks. Subcommittee D01.37 on Ink Vehicles
printing. Although an apparent tack measurement does not
assisted in the development of the vehicle portion of this test method.
Current edition approved Dec. 10, 1997. Published September 1998. Originally completely predict the transfer performance of an ink or a
published as D 4361 – 84. Last previous edition D 4361 – 89 (1996).
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D4361–97(Reapproved2002)
vehicle, it provides a meaningful parameter for quality control, initial boiling range of 250 to 350°F (120 to 177°C), a final
development, and research. boiling range of 300 to 400°F (150 to 205°C), a Kauri-Butanol
4.2 A given tackmeter will produce repeatable results on a value of 30 to 40 and less than 1 % benzene content are
day-to-day basis only if proper attention is paid to calibration appropriate for many sheet-fed and heat-set systems. Specific
and maintenance procedures and to control of experimental solvents may be required for unique systems.
variables referred to in 2.1.1.1. 7.2 Rags or Wipers, clean, soft, absorbent, lint-free.
4.3 Two or more instruments may not produce identical 7.3 Manufacturer’s Current Manual, for the specific model
apparent tack readings, but if each gives repeatable results, tackmeter.
they may be mathematically correlated.
8. Hazards
NOTE 1—Anumberofthree-rollertackmetersareavailablewhichdiffer
8.1 Never let an ink or a vehicle dry completely on the
in design features such as roller weight, geometry, and composition of the
rollers of the tackmeter. (Warning—Never turn the ZERO
distribution system. It cannot be presumed that test results from these
button except during the calibration process (see 12.2.1)).
other types of tackmeters will either agree or correlate with those from the
tackmeters specified in 6.1 and 6.2 of this test method.
8.2 Take care not to damage the rollers during the cleaning
process or by leaving them in contact when the instrument is
5. Interferences
not in use.
5.1 Tackmeter Squeal—Ahigh pitched whine or squeal may
8.3 Do not disengage the balance beam of a mechanical
be noted when running high tack fluids or at high rotating
model except when taking a reading.
speeds, or both. Squeal may result in instability of the balance
beam or direct reading attachment of mechanical models, or 9. Sampling and Test Specimen
fluctuation of the digital readout of electronic models, making
9.1 Carefully select a sample that is free of skin and other
definite readings difficult.
contamination and representative of the lot being evaluated. A
minimum of 3 to 4 mLis sufficient for two specimens.Transfer
6. Apparatus
to a clean container, protect with skin paper, close, and seal.
9.2 When ready to make a run (see 12.3), fill the ink pipet
6.1 Three-Roller Tackmeter—Models differ in available
as follows: Transfer 1.5 to 2 mL of sample to a clean glass
speeds and type of readout as follows:
plate; close and reseal the container. Gently work up with an
6.1.1 Mechanical Models, operate three or four fixed speeds
ink knife but do not aerate. Fill the ink pipet with 1.32 mL of
selected from among 400, 800, 1200, and 2000 r/min.Adirect
the worked sample (or with a smaller volume (0.5 to 1.0 mL)
reading attachment or a recorder is recommended to supple-
if a thinner film thickness is desired). Use the ink knife to force
ment the manually operated balance beam.
the specimen into the cylinder while slowly pulling back the
6.1.2 Electronic Models, operate at variable speeds ranging
ram. Wipe excess material off the top of the pipet.
from 100 to 2000 or 3000 r/min.Arecorder or printer, or both,
are recommended to supplement the digital readout.
NOTE 3—Aspecimen volume of 1.32 mL, divided by the roller surface
2 2
area of 0.010 ft (0.107 m ), gives an initial film thickness of 12.3 µm
NOTE 2—To convert to units of linear speed, multiply revolutions per
when distributed uniformly on the roller system. However, the occurrence
minute by 0.785 to obtain feet per minute or by 0.004 to obtain metres per
of appreciable flying or misting will result in loss of specimen from the
second.
rollers. Hence, operating film thickness is unknown.
6.2 Tackmeter Rollers, of suitable composition, preferably
one set for each major system to be evaluated (see 10.3.1.) A
10. Preparation and Conditioning of the Tackmeter
set consists of a top (measuring) roller 3 ⁄8 in. (79 mm) in
10.1 Locate the tackmeter on a sturdy bench in a draft-free
diameter and 6 ⁄8 in. (155 mm) in length, and a vibrator 2.0 in.
temperature-controlled environment, preferably 73.5 6 3.5°F
(51 mm) in diameter and 7 ⁄4 in. (184 mm) in length. Together
(23 6 2°C). Humidity control is necessary for test samples that
with the fixed brass roller, the total surface area of the
are moisture-sensitive or prone to misting.
2 2
distributionsystemis166in. (0.107m ).Themeasuringroller
10.2 Set the water bath at 90.0 6 0.2°F (32.2 6 0.1°C).All
weighs 9.2 lb (4.2 kg) on mechanical models and 9.6 lb (4.4
tests are to be run at this temperature. (See also A1.3.)
kg) on electronic models.
10.3 Prior to use, ascertain the nature of the test sample for
6.3 Ink Pipet, consisting of a metal cylinder and a metal or
the following reasons:
TFE-fluorocarbon plunger. Suitable pipets include fixed-
10.3.1 Roller conditioning—Use only an instrument having
volume pipets, 1.32-mL capacity; and variable volume mi-
rollers well broken in for the type of test system. The break-in
cropipets, 2-mL capacity, accurate to 0.01 mL.
procedure is given in A1.2. A separate set of broken-in rollers
6.4 Stopwatch or Timer, accurate to 1 s.
is mandatory for radiation curing systems. The necessity for
6.5 Ink Knife, small, free from nicks and rough edges.
separate sets of broken-in rollers, or for extensive recondition-
6.6 Manufacturer’s Calibration Apparatus, for the specific
ing when switching among different types of conventional test
model tackmeter.
systems shall be determined in each laboratory.
10.3.2 Operating speed—Vehicles are most commonly run
7. Reagents and Materials
at 400 r/min, alternatively at 800 r/min; sheet-fed inks at 800
7.1 Wash-Up Solvent, compatible with the test system, fast r/min, alternatively at 400 or 1200 r/min; and web-fed inks at
evaporating, and having minimal effect on the rollers; it should 1200r/min,alternativelyat800or2000r/min.(Theconversion
be acceptable environmentally. Hydrocarbon solvents with an to linear speed is given in Note 2.)
D4361–97(Reapproved2002)
10.4 Prior to the first use of the day, equilibrate the 12.4.1.2 Set the gears at 400 r/min, start the motor and the
tackmeter as follows: stopwatch simultaneously, and let the ink distribute for 15 s.
10.4.1 Warm up the instrument by activating the water Stop the motor but not the stopwatch.
cooling system. Engage the two composition rollers and run at 12.4.1.3 Quicklyswitchthegearstothetestspeed(specified
the lowest available speed for about 30 min. in10.3.2)andimmediatelyrestartthemotor,notingthetimeon
10.4.2 Make a conditioning run with a specimen represen- the stopwatch.
12.4.2 Mechanical Model MBC:
tative of the system to be evaluated. Apply 1 to 1.5 mL of the
ink or vehicle, and run for 5 to 10 min at the specified test 12.4.2.1 Place the fingertips against the sides of the brass
roller and manually turn about ten revolutions, or until the
speed (see 10.3.2). Clean up as directed in Section 13.
specimen appears evenly distributed among the three rollers.
Do not touch the surface of the rollers.
11. Calibration of the Tackmeter
12.4.2.2 Place the speed control switch at the 150 r/min
11.1 Calibrate the tackmeter before initial use and periodi-
position.Simultaneouslydepressthepowerswitchandstartthe
cally as needed. First, conduct the necessary steps in 10.3 and
stopwatch. Let the ink distribute for 15 s.
10.4.
12.4.2.3 Quickly reposition the speed control switch to the
11.2 Using the manufacturer’s calibration apparatus, follow
test speed, noting the time on the stopwatch.
the directions in the instrument manual.
12.4.3 Electronic Models:
11.2.1 Mechanical Models—Zero and calibrate the balance
12.4.3.1 Place the fingertips against the sides of the brass
beam (and direct reading attachment or recorder, if they are to
roller and manually turn about ten revolutions, or until the
be used) at the test speed specified in 10.3.2.
specimen appears evenly distributed among the three rollers.
11.2.2 Electronic Models—Zero and calibrate the digital
Do not touch the surface of the rollers.
readout (and recorder, if it is to be used) at 1000 r/min. When
12.4.3.2 Depress the DRIVE button and simultaneously
calibration is completed, check the dry reading at the specified
activate the stopwatch. Let the ink distribute for 15 s at the
test speed (see 10.3.2).
automatic LOW speed of 150 r/min.
NOTE 4—Three-roller tackmeters can be calibrated at only one speed.
12.4.3.3 Quickly switch to the test speed (preset in 12.1) by
depressing the HIGH/LOW button again, noting the time on
11.3 After each calibration or at regular periods, make a test
the stopwatch.
run with a standard ink or vehicle. (See A1.5.)
12.5 After 60 s of running at the test speed, record the
apparent tack of the test specimen from the balance beam (see
12. Procedure for Tack Evaluation
A1.4); direct-reading attachment, or the recorder of a mechani-
12.1 If necessary, make preparations as in 10.3 and 10.4,
cal model or the digital readout, recorder, or printer of an
and calibrate as in Section 11. If using an electronic model,
electronic model.
make sure the motor is preset to the test speed specified in
12.6 Optional—Rather than restrict the test to a single
10.3.2 and the drive is in the LOW mode.
apparent tack determination, valuable information may, in
12.2 Engagetherollersandrunatthespecifiedtestspeed.If
some cases, be gained by continuing the run, taking readings at
the dry reading differs from zero by more than 60.5 g-m,
uniform time intervals (facilitated by the use of a recorder)
reclean the rollers in accordance with 13.1 or recalibrate in
until the apparent tack begins to decrease. Alternative
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