Standard Practice for Preparing Prints of Paste Printing Inks with a Printing Gage

SIGNIFICANCE AND USE
4.1 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.
FIG. 1 Schematic Diagram of Printing Gages (not drawn to scale)  
4.2 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.  
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.
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautions are given in Section 7.  
1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

Status
Published
Publication Date
31-May-2020
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM D6846-02(2020) - Standard Practice for Preparing Prints of Paste Printing Inks with a Printing Gage
English language
4 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)


This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D6846 − 02 (Reapproved 2020)
Standard Practice for
Preparing Prints of Paste Printing Inks with a Printing Gage
This standard is issued under the fixed designation D6846; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
1.1 This practice covers the procedure for preparing labo- 2.1 ASTM Standards:
D1316 Test Method for Fineness of Grind of Printing Inks
ratory prints of paste inks using a printing gage in conjunction
By the NPIRI Grindometer
with a flat-bed proof press.
D6073 Test Method for Relative Setting of Heatset Printing
1.2 This practice is applicable to the preparation of solid-
Inks
area prints by direct letterpress or by dry offset on a flat
D6487 Practice for Preparing Prints of Paste Printing Inks
substrate such as paper, paperboard, or metal.
Using a Hand Operated Laboratory Flat-Bed Press
1.3 This practice is applicable primarily to lithographic and
3. Summary of Practice
letterpress inks that dry by oxidation or penetration. With the
addition of appropriate drying or curing equipment, it is also
3.1 The printing gage is inked by a drawdown technique; a
applicable to other paste ink systems such as heat-set or
double drawdown is recommended to minimize scratches and
energy-curable.
improve print appearance.
1.4 The instructions in this practice are intended to mini-
3.2 The inked gage is placed in the bed of the proof press
mize the within-print and among-operator variability inherent
from which the regular printing plate has been removed.
in hand operations.
3.3 To make a letterpress print, the appropriate stock is
1.5 This practice features built-in ink film thickness control.
attached to the impression (blanket) cylinder, which is rolled
It does not measure the film thickness transferred to the print;
once over the inked gage. To make a dry offset print, the stock
however, film thickness equivalence may be evaluated by
is clipped onto the impression plate and the blanket cylinder is
visual or instrumental comparisons of optical density.
rolled over the inked printing gage two to four times followed
by once over the stock.
1.6 Values stated in SI units are to be regarded as the
standard. The values given in parentheses are for information 3.4 Two-colorprintsmaybepreparedbyutilizingtwoinked
only. gages in the bed of an offset proofing press.
1.7 This standard does not purport to address all of the
4. Significance and Use
safety concerns, if any, associated with its use. It is the
4.1 Laboratory proofing of inks is necessary to establish a
responsibility of the user of this standard to establish appro-
reproducible prediction of print appearance and performance
priate safety, health, and environmental practices and deter-
properties, most of which are highly sensitive to ink film
mine the applicability of regulatory limitations prior to use.
thickness. The apparatus described in this practice has found
Specific precautions are given in Section 7.
wide use for routine control proofing because it provides an
1.8 This international standard was developed in accor-
economical method for producing reasonably large prints at
dance with internationally recognized principles on standard-
film thicknesses comparable to those obtained on production
ization established in the Decision on Principles for the
presses.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
4.2 Aunique advantage of printing gages is that, depending
Barriers to Trade (TBT) Committee.
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
This practice is under the jurisdiction of ASTM Committee D01 on Paint and
Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.56 on Printing Inks. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
CurrenteditionapprovedJune1,2020.PublishedJuly2020.Originallyapproved contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
in 2002. Last previous edition approved in 2012 as D6846 – 02 (2012). DOI: Standards volume information, refer to the standard’s Document Summary page on
10.1520/D6846-02R20. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6846 − 02 (2020)
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 2 25 × 159 89 × 241 0-1.0 0-25 0-20
NPIRI-B 2 38 × 159 114 × 241 0-0.6 0-15 0-12
Uniform Film Thickness, Single Depth
D D
Warren-2 1 76 × 165 102 × 165 0.3 7 ⁄2 6
D D
Warren-3 1 76 × 165 102 × 165 0.4 10 8
D D
Warren-4 1 76 × 165 102 × 165 0.5 12 ⁄2 10
D D
Warren-5 1 76 × 165 102 × 165 0.6 15 12
Huber-2 1 63 × 152 89 × 152 0.8 20 16
E E
BSI-10 2 51 × 165 140 × 165 0.4 10 8
E E
Lindner 2 51 × 165 140 × 165 0.6 15 12
F
Uniform Film Thickness, Three Depths
FPBAA-C 3 38 × 102 165 × 102 0.2 5 4
0.4 10 8
0.6 15 12
6960-1 3 38 × 102 165 × 102 0.2 5 4
0.3 7 ⁄2 6
0.4 10 8
6960-2 3 38 × 102 164 × 102 0.5 12 ⁄2 10
0.6 15 12
0.7 17 ⁄2 14
Combination Uniform and Tapered Film Thickness
6401 2 51 × 203 153 × 203 0.6 15 12
51 × 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 D1316.
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.
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 specified, the cylinder of the press must be capable of making
clean up. In addition, problems due to ink distribution systems two revolutions down the length of the bed, as in Practice
are eliminated, two inks may be proofed at the same time, and D6487.
multi-color printing is possible.
5.4 Ink Knife, small.
4.3 This practice does not duplicate the dynamics of a high
5.5 Accelerated Drying Equipment (Optional), for example,
speedpress,nevertheless,itisusefulforqualitycontrolandfor
source of heat as in Test Method D6073 or energy-curing, as
specification acceptance between the producer and the user.
appropriate to the system.
5.6 Print Quality Measuring Equipment (Optional), as de-
5. Apparatus
scribed in Practice D6487 or as agreed upon between producer
5.1 Printing Gage, consisting of a type-high (approxi-
and user.
mately 23.3 mm, 0.918 in.) block of steel, the top surface of
which contains precision-machined channels that may be
6. Materials
tapered in depth similar in principle to the grind gages
6.1 Reference Standard (Optional), such as an ink sample,
described in Test Method D1316. 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 Drawdown Blade, having a length sufficient to span
printing gage and 0.5 or 1 mil in thickness.
the 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
use.
The sole source of supply of the apparatus known to the committee at this time
is Precision Gage and Tool Co., 375 Gargrave Rd., Dayton, Oh 45449. If you are 7. Hazards
aware of alternative suppliers, please provide this information to ASTM Interna-
7.1 Warning—Since solvents may be hazardous to the skin
tional Headquarters.Your comments will receive careful consideration at a meeting
of the responsible technical committee, which you may attend. and eyes, wear rubber gloves and safety glasses during cleanup
-----
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.