ASTM D4942-89(2001)
(Test Method)Standard Test Methods for Water Pickup of Lithographic Printing Inks and Vehicles in a Laboratory Mixer
Standard Test Methods for Water Pickup of Lithographic Printing Inks and Vehicles in a Laboratory Mixer
SCOPE
1.1 These test methods cover two procedures for determining the amount of water picked up by lithographic printing inks in a laboratory mixer.
1.2 Test Method A covers single-point water pickup; Test Method B covers the rate of water pickup. Both test methods are applicable to any printing ink and vehicle intended for the lithographic printing process.
1.3 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.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D4942–89 (Reapproved 2001)
Standard Test Methods for
Water Pickup of Lithographic Printing Inks and Vehicles in a
Laboratory Mixer
This standard is issued under the fixed designation D 4942; 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 3.3 The emulsions obtained in these test methods are of
larger particle size than those typically produced in printing
1.1 These test methods cover two procedures for determin-
nips. Because of these and other variables in the printing
ingtheamountofwaterpickedupbylithographicprintinginks
process, water pickup results do not by themselves predict
in a laboratory mixer.
lithographic printing performance.
1.2 Test Method A covers single-point water pickup; Test
Method B covers the rate of water pickup. Both test methods
4. Apparatus
are applicable to any printing ink and vehicle intended for the
4.1 Laboratory Mixer, such as a Duke Ink-Water Emulsi-
lithographic printing process.
fication Tester equipped with a stainless steel specimen bowl
1.3 This standard does not purport to address all of the
83 mm wide and 88 mm high, mixer blades that rotate at 90
safety concerns, if any, associated with its use. It is the
r/min, and a timing device.
responsibility of the user of this standard to establish appro-
4.2 Balance, accurate to 0.1 g, 600-g capacity.
priate safety and health practices and determine the applica-
4.3 Palette knives, two.
bility of regulatory limitations prior to use.
4.4 Thermometer, quick response.
2. Summary of Test Methods 4.5 pH Meter (optional).
4.6 Conductivity Meter (optional).
2.1 Thesetestmethodsutilizealaboratorymixerforbeating
4.7 Graduated Cylinder, 50 or 100-mL.
water or other agreed upon fluid into the test ink.
2.2 For single-point water pickup (Test Method A), 50 mL
5. Reagents and Materials
of water is normally added to 50 g of ink and mixed in for 5
5.1 Water—Deionized or distilled water, preferably having
min. The water picked up is determined from volumetric
a pH of 5.0 to 7.0 (100 to 200 mL per sample); alternatively,
measurements of free water.
fountain solution or other aqueous medium as agreed upon
2.3 Forrateofwaterpickup(TestMethodB),waterisadded
between the supplier and the customer may be used.
to 50 g of ink in increments of 20 mL and mixed in for 1 min
5.2 Cleanup Materials—Naptha and rags or tissues.
or more over a cumulative time period totaling 10 min. The
water taken up by the ink after each mixing interval is
6. Test Specimen
determined gravimetrically.
6.1 A minimum of 100 g is sufficient for two determina-
tions. Before removing ink from the can, stir or otherwise
3. Significance and Use
ensure that the ink specimen is representative. Close the can
3.1 The lithographic printing process requires that some
and replace sealing tape immediately after each ink removal.
dampening solution be emulsified into the ink. These test
methods provide a rapid means for determining water pickup
7. Conditioning
under laboratory conditions. Test results may be useful for
7.1 Condition the instrument, water, and ink samples in a
specification acceptance between the supplier and the cus-
constant temperature room or bath, preferably at 23 6 1°C.
tomer.
7.2 Prior to use, check the alignment of the mixer blades.
3.2 In order that results be comparable, the tests must be run
With the power switch of the mixer in the off position, set the
at the same temperature and with the same type and quantity of
clean bowl into the turntable and engage the locking pin firmly
liquid added prior to mixing.
into the slot in the side of the turntable. Tilt the mixer head
back and insert the blades, marked left and right, into their
This test method is under the jurisdiction of ASTM Committee D01 on Paint
and Related Coatings, Materials, andApplications and is the direct responsibility of
Subcommittee D01.56 on Printing Inks. Available from Duke Custom Systems, 8371 Highway 49, Pleasant View, TN
Current edition approved April 28, 1989. Published June 1989. 37146.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D4942
times ten determinations. Intervals need not be uniform, for example, 1, 2,
respective holders. Lower the mixer head. If the blades hit the
3, 5, and 10 min (90 times 3 plus 180 plus 450 revolutions).
side or bottom of the bowl, return the instrument to the
manufacturer for realignment.
9.2 Optional—Measure water properties in accordance with
8.2.
8. Test Method A—Single Point Water Pickup (by
9.3 Weigh or tare the clean dry mixing bowl and blades on
Volumetry)
the balance. Add 50 6 0.1 g of ink to the center of the bowl.
9.4 Lock the bowl on the platform of the mixer. With the
8.1 Program the counter of the mixer for 5 min mixing time
mixer head raised, carefully insert the blades into their respec-
(450 revolutions).
tive holders. If ink on one blade touches the upper parts of the
8.2 Optional—If the first run of the day, pour test water into
other blade or the side of the bowl, carefully remove the ink
a beaker. Measure pH, conductivity, and temperature at the
with two palette knives and transfer to the bottom of the bowl.
beginning of testing.
Lower the mixer head.
8.3 Weigh or tare the clean dry mixing bowl.Add 50 6 0.1
9.5 Pour 100 mL of water (from 8.2) into a beaker. Meter
g of the ink to the center of the bowl.
out 20 mL and add to the bowl.
8.4 Pour 50 mL of water (from 8.2) into a graduated
9.6 Press the counter reset button, making sure that the
cylinder. If the ink is expected to pick up more than 100 %
desired number of revolutions is displayed on the face of the
water, use 100 mL of water. Adjust the volume to 60.5 mL.
counter. Turn the mixer on. Examine the contents of the bowl
Add the entire contents to the bowl.
as mixing progresses. If all liquid disappears into the ink, add
8.5 With the mixer head tilted back insert the clean blades,
more as needed to maintain a layer of excess water on the
marked left and right, into their respective holders. Lock the
surface of the ink.
bowl on the turntable. Lower the mixer head. Press the counter
reset button, making sure that 450 is displayed on the face of
NOTE 4—Few specimens will take up more than 20 mLof water within
the counter.
a 1-min mixing interval. If a high-water pickup specimen is being run and
8.6 Turn the mixer on. Examine contents of the bowl as
the mixing interval is longer than 1 min, another 20 mL should be added
prior to each subsequent minute of mixing time.
mixing progresses. If 50 mL of water had been added and all
of it disappears into the ink, stop, discard the ink in the bowl,
9.7 When the mixer stops, turn the power switch off. Detach
clean up, and start over from 8.3, adding 100 mL of water in
the mixing blades and add to the bowl.
8.4. The latter quantity must also be used for all other inks in
9.8 Remove the bowl from the turntable and, holding the
the series under study.
blades at the side of the bowl, decant the free water into the
beaker containing the unused water. Run the bladesveryslowly
NOTE 1—With some inks, water p
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.