SMART DESIGN

LABELS&LABELING |41
Hammer looks
to G7 future
G7 CERTIFICATION FOR THE PACKAGING INDUSTRY is the ticket for a brand’s print buyer to ensure
consistency across variables and offers other benefits, writes Danielle Jerschefske
Hammer Packaging in Rochester, New York, is one of the
first packaging printers in North America to achieve G7
Master Printer Status, a qualification granted by IDEAlliance,
a non-profit industry association which disseminates best
practice methodologies, specifications and standards for the
print industry.
When it comes to print consistency across a brand-marketing
portfolio, print buyers have traditionally found it difficult
to match color across different regions or across different
print types and materials. For the packaging industry, G7
represents a radically different approach to this problem.
Because Hammer produces printed labels and package
decorations for the global beverage, food, horticulture
and household products industries, including cut & stack,
in-mold, shrink sleeve, roll-fed and pressure sensitive
labels, it was eager to reap the benefits found in the G7
methodology.
Essentially G7, or Near-Neutral Calibration, defines targets
that allow packaging printers to match a proof to a press; a
press to a press; one process to another; and across various
consumables. The ‘G’ stands for gray as in gray balance
or neutrality, and the ‘7’ refers to the seven major process
printing colors.
G7 uses colorimetry to specify both the color of the media,
in white point, and the color of the inks in accordance with
ISO 12647-2, which describes gray balance as 50/40/40
CMY. The resulting grayscale and tonal curve is used for
calibrating a proofing and/or printing system. G7 utilizes the
new ISO 10128 standard to set near-neutral calibration.
Rather than changing the tint by diluting color with white
or black ink, a grayscale-based system adjusts the tone,
where the eye is more sensitive than saturated color. All a G7
certified converter like Hammer has to do is maintain gray
balance and tone within this set range.
BENEFITS TO BRAND AND CONVERTER
Lou Iovoli, Hammer’s VP strategic partnerships and
marketing, says, ‘The advantage to the brand owner is that
we can provide our press 'condition' to a given designer so
they can provide customers with a proof that will match the
final print image from our press. In this way our customers
will know sooner what a design will look like, rather than
having to wait or travel for a press approval.’
Hammer started using the G7 process to control both
press and proofing in Fall 2010. Iovoli says, 'With this
process we are able to map the wide gamut of colors used
in packaging and produce a proof that represents the press
condition. This process takes into consideration the various
combinations of substrate and inking in either surface or
reverse printing. We strive to reduce the uncertainty of the
proof matching the printed sample, allowing us to deliver
high quality products for our customers.'
A second benefit is that the print file no longer needs to
be modified or adjusted to print to any of Hammer's presses
regardless of the printing process or consumables used. This
can mean significant cost savings since one file can be used
for everything: cartons, labels, a webpage, POP and flexible
packaging.
If all the print products have the same gray balance and neutral
tonality defined by G7, they will all look remarkably alike to the
human eye. Since buyers believe the similarity of the visual
appearance across print products is critical, and are gaining a
better understanding of the G7 method, many have started to
make G7 a buying requirement.
Lastly, G7 calibration gives print buyers flexibility in processes
and materials used in the packaging industry. It streamlines the
coordination between the pre-press house and printer thereby
improving speed to market.
THE STEPS
G7 defines the print condition in two ways – tone reproduction,
gray scale – and it describes how to use the principles of digital
imaging, spectrophotometry, and computer-to-plate (CtP)
technologies to achieve color matches using quality inks and
papers. Its Neutral Print Density Curve (NPDC) defines the
neutral density of the grayscale curve with a combined CMY
curve of 50/40/40 at the middle tone and specifies the tone from
highlight to shadow, taking priority over traditional TVI curves. The
calibration method calculates corrected RIP values that will force
the press to replicate the desired NPDC curve based on the given
press conditions.
As the NPDC curve approaches the solids then the lines will
deviate. Gray process control patches should always be printed on
the production runs in order to regularly verify gray balance. It is
important to remember that gray balance tells the printer that the
JULY 2012 | L&L