BXP - May 2018 - 24
A D V E R T O R I A L
Secrets of achieving high fidelity print
reproduction on box grade plastics.
Unlike paperboard, box-grade plastics are non-absorbent,
heat sensitive and transparent. Therefore, they require a
significantly different approach to printing.
Non-Absorbent - Conventional inks cannot dry on plastic
by absorption into the substrate like they can on paperboard, so UV ink systems must be used. UV inks contain
photoinitiators that, when exposed to high amounts of UV
light, cure instantly and adhere well to plastic substrates.
Transparent - Standard inks appear translucent on clear
plastic. For opaque graphics, color printing must be backed
up with white inks, so what might be a six-color print job
on paperboard might be eight or more colors on plastic.
Because plastic is transparent, customer-facing graphics can
be printed on the exterior of the substrate, on the interior,
or on both.
Heat Sensitive - UV curing generates heat, which can
distort plastic substrates, so controlling substrate temperature is critical. Typically, printing presses used for plastics
have been modified to introduce a method to cool the
sheets. Without managing heat, printing and die-cutting
accuracy would suffer.
HLP Klearfold is the clear plastic packaging market and
technology leader. The company has earned a well-deserved
reputation for extremely advanced UV print reproduction,
providing exceptional quality offset, silkscreen, and flexo
printing for the highest fidelity printed graphics available
on plastic folding cartons. Its most recently acquired press
represents a technology step-change in the manufacture of
premium-quality clear packaging products.
The 26" wide, 13-color, web-fed printing press has a
rotogravure station and 12 web-flexo stations. To print on
both sides of the web at once, up to five of the flexo stations
can be configured for backside printing. There are also
four rotary silkscreen and two cold foil units that can be
interchanged with any of the flexo stations. The new press
provides extreme flexibility and allows HLP Klearfold to
accomplish in a single printing pass, what would have
required five or more passes using traditional UV offset
printing, with off-line silkscreen printing and foil stamping.
In addition to greatly enhanced efficiency, the press delivers
greatly enhanced results. UV flexo printing provides thicker
ink films than does offset printing and, on plastic, that
means bolder, more vibrant, and more opaque colors. UV
flexo also offers excellent color stability and exceptional
four-color process printing with up to 200-line screens for
high-fidelity photographic print reproduction.
The rotary silkscreen printing can produce a raised,
tactile effect or provide a very effective "insulating" layer,
preventing the show-through of graphics printed on both
the front and backside of a transparent substrate.
Finally, the rotary cold foil stations serve to provide
additional aesthetic enhancement and, by applying cold
foil on the round, eliminate gas trapping for a smoother
application, even on large foil areas. And foil is easily
over-printed with transparent UV flexo inks for an infinite
spectrum of color possibilities.
For more information on visual package printing
on box grade plastics, especially on HLP Klearfold's
leading edge web-flexo press, visit:
or call 888 457-7225 for samples.
HLP Klearfold's remarkable new 13color web-flexo printing press provide
exceptional print quality and far more
printing and decorating options.