Standard Practice for Preparing Prints of Paste Printing Inks Using a Hand Operated Laboratory Flat-Bed Press

SIGNIFICANCE AND USE
4.1 Laboratory proofing of ink 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.  
4.2 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 where there is an agreed upon specification for reflection density or standard reference print.
SCOPE
1.1 This practice covers the procedure for preparing prints of paste inks using a hand operated flat-bed laboratory proof press. The initial method was developed by the National Printing Ink Research Institute.2  
1.2 This practice is applicable to the preparation of single-color solid-area prints by the dry offset process (also known as Letterset) on a flat substrate such as paper or metal. It can readily be adapted to print by direct letterpress.3
Note 1: The proofing press described in this practice can also be used with printing gages in accordance with Practice D6846.  
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 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 does not measure the actual film thickness on the print, but evaluates film thickness equivalence by visual or instrumental comparisons of reflection density.  
1.6 The 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 users 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.

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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: D6487 − 10 (Reapproved 2019)
Standard Practice for
Preparing Prints of Paste Printing Inks Using a Hand
Operated Laboratory Flat-Bed Press
This standard is issued under the fixed designation D6487; 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 1.8 This international standard was developed in accor-
dance with internationally recognized principles on standard-
1.1 This practice covers the procedure for preparing prints
ization established in the Decision on Principles for the
of paste inks using a hand operated flat-bed laboratory proof
Development of International Standards, Guides and Recom-
press. The initial method was developed by the National
2 mendations issued by the World Trade Organization Technical
Printing Ink Research Institute.
Barriers to Trade (TBT) Committee.
1.2 This practice is applicable to the preparation of single-
color solid-area prints by the dry offset process (also known as
2. Referenced Documents
Letterset) on a flat substrate such as paper or metal. It can
2.1 ASTM Standards:
readily be adapted to print by direct letterpress.
D6073 Test Method for Relative Setting of Heatset Printing
NOTE 1—The proofing press described in this practice can also be used
Inks
with printing gages in accordance with Practice D6846.
D6846 Practice for Preparing Prints of Paste Printing Inks
1.3 This practice is applicable primarily to lithographic and
with a Printing Gage
letterpress inks that dry by oxidation or penetration. With the
D7305 Test Method for Reflection Density of Printed Matter
addition of appropriate drying or curing equipment, it is also
2.2 ANSI Standards:
applicable to other systems such as heat-set or energy-curable.
PH 2.30 Viewing Conditions for Graphic Arts and
1.4 The instructions in this practice are intended to mini-
Photography—Color Prints,Transparencies and Photome-
mize the within-print and among-operator variability inherent
chanical Reproductions
in hand operations.
CGATS.5 Graphic Technology–Spectral Measurements and
Colormetric Computation for Graphics Arts Images
1.5 This practice does not measure the actual film thickness
on the print, but evaluates film thickness equivalence by visual
3. Summary of Practice
or instrumental comparisons of reflection density.
1.6 The values stated in SI units are to be regarded as the 3.1 Prints are prepared by metering the test ink onto a
standard. The values given in parentheses are for information brayer, rolled out evenly, on the distribution plate according to
only. a specified pattern, and then transferred to the printing plate.
The substrate is clipped onto the impression plate, and the
1.7 This standard does not purport to address all of the
blanket cylinder is rolled over the inked plate six times
safety concerns, if any, associated with its use. It is the
followed by once over the substrate.
responsibility of the users of this standard to establish appro-
priate safety, health, and environmental practices and deter-
3.2 After the print is dry to the touch, it is evaluated versus
mine the applicability of regulatory limitations prior to use.
the target reflection density instrumentally or by visual com-
Specific precautions are given in Section 7.
parison with a standard reference print. Subsequent prints can
be made if the target reflection density has not been achieved
or if a visual assessment indicates that either more or less ink
is needed.
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.
Current edition approved Jan. 1, 2019. Published January 2019. Originally
approved in 1999. Last previous edition approved in 2010 as D6487 – 10. DOI: For referenced ASTM standards, visit the ASTM website, www.astm.org, or
10.1520/D6487-10R19. contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
“The NPIRI Standard Procedure for Preparing Little Joe Prints,” American Ink Standards volume information, refer to the standard’s Document Summary page on
Maker, March 1994, pp. 42-50. the ASTM website.
3 5
The apparatus used to develop this method was the Little Joe Offset Color Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
Proofing Press. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D6487 − 10 (2019)
4. Significance and Use 7. Hazards
4.1 Laboratory proofing of ink is necessary to establish a 7.1 Warning—Since solvents may be hazardous to the skin
reproducible prediction of print appearance and performance and eyes, wear rubber gloves and safety glasses during cleanup
properties, most of which are highly sensitive to ink film to avoid solvent contact with skin and eyes. See supplier’s
thickness. The apparatus described in this practice has found Safety Data Sheets for further information on each solvent
wide use for routine control proofing because it provides an used.
economical method for producing reasonably large prints at
7.2 Equipment Cautions—Avoid any operation that will
film thicknesses comparable to those obtained on production
scratch the metal distribution and printing plates or damage the
presses.
rubber blanket on the impression cylinder.
4.2 This practice does not duplicate the dynamics of a high
speed press, nevertheless, it is useful for quality control and for
8. Flatbed Press Set Up
specification acceptance between the producer and the user
8.1 Prepare the proof press as described in Annex A1 as
where there is an agreed upon specification for reflection
seen in Fig. A1.1.
density or standard reference print.
9. Procedure for Dry Offset Printing (Letterset)
5. Apparatus
9.1 Inspect and ensure that the printing plate, blanket and
5.1 Laboratory Flat-Bed Proof Press , having a press bed
print roll out area are clean and free from lint.
approximately 914 mm (36 in.) long and 260 mm (10 ⁄4 in.)
9.2 Place guide tracks against printing plate and place a 140
wide, and a blanket (impression) cylinder having a circum-
1 1
by 210-mm (5 ⁄2 by 8 ⁄2 in.) piece of test substrate on the
ference of approximately 370 mm (14 ⁄2 in.) such that the
impression plate.
cylinder can make two revolutions down the length of the bed.
Integral components include a distribution plate, printing plate,
9.3 Determine the approximate amount of ink that will give
inking track guides, and impression plate (see Fig. A1.1). The
the proper density. If uncoated paper, start with 0.6 mL or 0.6
standard printing plate is 100 by 152 mm (4 by 6 in.).
g of ink. For coated paper, start with 0.4 mL or 0.4 g of ink.
5.2 Ink Pipette, or balance accurate to 0.001 g ink.
9.4 Using an ink knife or a pipette, apply the ink to the
brayer evenly across the roller.
5.3 Torque Screw Driver.
9.5 Roll the ink on the distribution plate with the brayer
5.4 Ink Knives.
until a uniform ink film is created and the entire distribution
5.5 Brayer, with a 63.5-mm (2 ⁄2-in.) diameter and 152-mm
plate has been used.
(6-in.) length.
9.6 Once a uniform film exists, roll the brayer from corner
5.6 Standard Daylight, preferably a D 50 light source con-
to corner of the ink distribution plate to make a single “X”
forming to ANSI Standard PH 2.30.
pattern. Then move the brayer from top to bottom and bottom
5.7 Reflection Densitometer (optional), conforming to Test to top without lifting (2 passes) along the middle of the
Method D7305.
distribution plate. Turn brayer 180° (feet to point in opposite
direction) and repeat “X” pattern and top to bottom and bottom
NOTE 2—The filter systems in typical densitometers are suitable only
to top motion.
for use with black, white, and the three process colors (yellow, magenta
and cyan).
9.7 Apply ink to printing plate with six passes of brayer
5.8 Spectrophotometer (optional), calibrated according to using a smooth motion (one pass is motion in one direction
manufacturer’s instructions and used according to CGATS.5. only, left to right or right to left). Do not lift brayer between
passes. Pressure applied will depend on the ink rheology but
6. Materials last pass (dressing pass) should be less than the pressure for the
previous five passes. Push guide tracks away from printing
6.1 Ink Sample.
plate.
6.2 Reference Print (optional).
9.8 Repeat 9.6 and 9.7 to ink the brayer and again apply ink
6.3 Printing Substrate cut to approximately 140 by 210 mm
to the printing plate. Push guide tracks away from printing
1 1
(5 ⁄2 by 8 ⁄2 in.).
plate.
6.4 Solvent, appropriate to ink system.
9.9 Apply ink to the blanket by engaging cylinder, and pass
in forward motion over printing plate stopping before the
6.5 Lint-free Rags or Tissue.
impression plate. Disengage cylinder and return.
6.6 Shim Stock, metal or plastic, the same size as the
9.10 Repeat 9.9 (apply ink to the blanket) for six blanket
printing plate and 0.5, 1, 2, 5 or 10 mils in thickness.
passes over the printing plate (blanket is inked in forward
motion only).
9.11 Repeat 9.6 (inking the brayer), 9.7 (inking the printing
For printing ultra violet (UV) systems, use a special blanket and brayer
formulated for the purpose. p
...

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