ASTM D6846-02
(Practice)Standard Practice for Preparing Prints of Paste Printing Inks with a Printing Gage
Standard Practice for Preparing Prints of Paste Printing Inks with a Printing Gage
SIGNIFICANCE AND USE
Laboratory proofing of inks is necessary to establish a reproducible prediction of print appearance and performance properties, most of which are highly sensitive to ink film thickness. The apparatus described in this practice has found wide use for routine control proofing because it provides an economical method for producing reasonably large prints at film thicknesses comparable to those obtained on production presses.
A unique advantage of printing gages is that, depending on the design selected, prints can be produced at a range of tapered film thicknesses or at several levels of uniform thicknesses in a single proofing. Because of the built-in film thickness control, ink metering is not necessary. Relatively small quantities of test samples are used, and less than two minutes are required to ink a gage, pull a letterpress print, and clean up. In addition, problems due to ink distribution systems are eliminated, two inks may be proofed at the same time, and multi-color printing is possible.
This practice does not duplicate the dynamics of a high speed press, nevertheless, it is useful for quality control and for specification acceptance between the producer and the user.
FIG. 1 Schematic Diagram of Printing Gages (not drawn to scale)
SCOPE
1.1 This practice covers the procedure for preparing laboratory prints of paste inks using a printing gage in conjunction with a flat-bed proof press.
1.2 This practice is applicable to the preparation of solid-area prints by direct letterpress or by dry offset on a flat substrate such as paper, paperboard, or metal.
1.3 This practice is applicable primarily to lithographic and letterpress inks that dry by oxidation or penetration. With the addition of appropriate drying or curing equipment, it is also applicable to other paste ink systems such as heat-set or energy-curable.
1.4 The instructions in this practice are intended to minimize the within-print and among-operator variability inherent in hand operations.
1.5 This practice features built-in ink film thickness control. It does not measure the film thickness transferred to the print; however, film thickness equivalence may be evaluated by visual or instrumental comparisons of optical density.
1.6 Values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.7 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. Specific precautions are given in Section 7.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:D6846–02
Standard Practice for
Preparing Prints of Paste Printing Inks with a Printing Gage
This standard is issued under the fixed designation D 6846; 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 D 6073 TestMethodforRelativeSettingofHeatsetPrinting
Inks by the Sinvatrol Tester
1.1 This practice covers the procedure for preparing labo-
D 6487 Practice for Preparing Prints of Paste Printing Inks
ratory prints of paste inks using a printing gage in conjunction
with an Offset Color Proofing Press
with a flat-bed proof press.
1.2 This practice is applicable to the preparation of solid-
3. Summary of Practice
area prints by direct letterpress or by dry offset on a flat
3.1 The printing gage is inked by a drawdown technique; a
substrate such as paper, paperboard, or metal.
double drawdown is recommended to minimize scratches and
1.3 This practice is applicable primarily to lithographic and
improve print appearance.
letterpress inks that dry by oxidation or penetration. With the
3.2 The inked gage is placed in the bed of the proof press
addition of appropriate drying or curing equipment, it is also
from which the regular printing plate has been removed.
applicable to other paste ink systems such as heat-set or
3.3 To make a letterpress print, the appropriate stock is
energy-curable.
attached to the impression (blanket) cylinder, which is rolled
1.4 The instructions in this practice are intended to mini-
once over the inked gage. To make a dry offset print, the stock
mize the within-print and among-operator variability inherent
is clipped onto the impression plate and the blanket cylinder is
in hand operations.
rolled over the inked printing gage two to four times followed
1.5 This practice features built-in ink film thickness control.
by once over the stock.
It does not measure the film thickness transferred to the print;
3.4 Two-colorprintsmaybepreparedbyutilizingtwoinked
however, film thickness equivalence may be evaluated by
gages in the bed of an offset proofing press.
visual or instrumental comparisons of optical density.
1.6 Values stated in SI units are to be regarded as the
4. Significance and Use
standard. The values given in parentheses are for information
4.1 Laboratory proofing of inks is necessary to establish a
only.
reproducible prediction of print appearance and performance
1.7 This standard does not purport to address all of the
properties, most of which are highly sensitive to ink film
safety concerns, if any, associated with its use. It is the
thickness. The apparatus described in this practice has found
responsibility of the user of this standard to establish appro-
wide use for routine control proofing because it provides an
priate safety and health practices and determine the applica-
economical method for producing reasonably large prints at
bility of regulatory limitations prior to use. Specific precau-
film thicknesses comparable to those obtained on production
tions are given in Section 7.
presses.
2. Referenced Documents 4.2 Aunique advantage of printing gages is that, depending
on the design selected, prints can be produced at a range of
2.1 ASTM Standards:
tapered film thicknesses or at several levels of uniform
D 1316 Test Method for Fineness of Grind of Printing Inks
2 thicknesses in a single proofing. Because of the built-in film
by the NPIRI Grindometer
thickness control, ink metering is not necessary. Relatively
small quantities of test samples are used, and less than two
This practice is under the jurisdiction of ASTM Committee D01 on Paint and minutes are required to ink a gage, pull a letterpress print, and
Related Coatings, Materials and Applications and is the direct responsibility of
clean up. In addition, problems due to ink distribution systems
Subcommittee D01.56 on Printing Inks.
are eliminated, two inks may be proofed at the same time, and
Current edition approved Dec. 10, 2002. Published February 2003.
multi-color printing is possible.
Annual Book of ASTM Standards, Vol 06.02.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D6846–02
A
TABLE 1 Popular Models of Printing Gages
Dimensions Dimensions
Ink Film Thickness
of Each of Gage
Number
B
Model
Machined Calibrated
Path Top
of Paths
mm mm mils µm µm
Tapered Film Thickness
C
NPIRI-A 225 3 159 89 3 241 0-1.0 0-25 0-20
NPIRI-B 2 38 3 159 114 3 241 0-0.6 0-15 0-12
Uniform Film Thickness, Single Depth
D D
Warren-2 1 76 3 165 102 3 165 0.3 7 ⁄2 6
D D
Warren-3 1 76 3 165 102 3 165 0.4 10 8
D D
Warren-4 1 76 3 165 102 3 165 0.5 12 ⁄2 10
D D
Warren-5 1 76 3 165 102 3 165 0.6 15 12
Huber-2 1 63 3 152 89 3 152 0.8 20 16
E E
BSI-10 2 51 3 165 140 3 165 0.4 10 8
E E
Lindner 2 51 3 165 140 3 165 0.6 15 12
F
Uniform Film Thickness, Three Depths
FPBAA-C 3 38 3 102 165 3 102 0.2 5 4
0.4 10 8
0.6 15 12
6960-1 3 38 3 102 165 3 102 0.2 5 4
0.3 7 ⁄2 6
0.4 10 8
6960-2 3 38 3 102 164 3 102 0.5 12 ⁄2 10
0.6 15 12
0.7 17 ⁄2 14
Combination Uniform and Tapered Film Thickness
6401 2 51 3 203 153 3 203 0.6 15 12
51 3 159 0-0.6 0-15 0-12
A
All models have paths ca. 23.3 mm (0.918 in.) high, parallel to bottom face.
B
Calibrated microns listed are based on 80 % path fillage for normal paste inks.
Fillage for thinner inks is less.
C
This model serves as a type-high grindometer in Test Method D 1316.
FIG. 1 Schematic Diagram of Printing Gages (not drawn to scale)
D
Also available in a 190 mm length.
E
Also available in a 203 mm length.
F
Each path has a uniform depth, but the depth is different in each path. Any
other combination may be ordered.
4.3 This practice does not duplicate the dynamics of a high
speed press, nevertheless, it is useful for quality control and for
specification acceptance between the producer and the user.
5.6 Print Quality Measuring Equipment (Optional),asde-
5. Apparatus
scribedinPracticeD 6487orasagreeduponbetweenproducer
and user.
5.1 Printing Gage, consisting of a type-high (approxi-
mately 23.3 mm, 0.918 in.) block of steel, the top surface of
6. Materials
which contains precision-machined channels that may be
tapered in depth similar in principle to the grind gages
6.1 Reference Standard (Optional), such as an ink sample,
described in Test Method D 1316. Alternatively, the channels
reference print, or a target level of quality attribute.
may be uniform in depth at one or more levels. See Fig. 1 for
6.2 Printing Substrate, cut to slightly more than the dimen-
schematic diagrams of the two types of gages.Adescription of
sions of the gage top cited in Table 1.
popular models is given in Table 1.
6.3 Shim Stock, metal or plastic, the same size as the
5.2 DrawdownBlade, having a length sufficient to span the
printing gage and 0.5 or 1 mil in thickness.
width of the printing gage being used.
6.4 Wash-upMaterials, including lint-free rags or tissue and
5.3 Flat Bed Proof Press, with a bed wide enough to
an appropriate solvent.
accommodate the printing gage. If proofing by dry offset is
6.5 Grease, to protect top face of printing gage when not in
specified, the cylinder of the press must be capable of making
use.
two revolutions down the length of the bed, as in Practice
D 6487.
7. Hazards
5.4 Ink Knife, small.
7.1 Warning—Since solvents may be hazardous to the skin
5.5 Accelerated Drying Equipment (Optional), for example,
and eyes, wear rubber gloves and safety glasses during cleanup
source of heat as in Test Method D 6073 or energy-curing, as
to avoid solvent contact with skin and eyes. In case of contact,
appropriate to the system.
wash skin with water; flush eyes for 15 min with water and call
a physician. See supplier’s Material Safety Data Sheets for
further information on each solvent used.
The sole source of supply of the apparatus known to the committee at this time
7.2 Equipment Cautions:
is Precision Gage and Tool Co., 375 Gargrave Rd., Dayton, Oh 45449. If you are
7.2.1 Avoid any operation that will scratch or damage the
aware of alternative suppliers, please provide this information to ASTM Interna-
printing gage and the blade. Refer to Test Method D 1316 for
tional Headquarters.Your comments will receive careful consideration at a meeting
of the responsible tec
...
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