100%

Paper Technology International 2023 - Flipbook - Page 81

PAPERTECHNOLOGYINTERNATIONAL
Omya Calcium Carbonate is Pushing Boundaries in Packaging Board - Paper Technology International 2023
The Omya Aqurate coating pigment product family
addresses the needs of packaging board manufacturers and
converters. Omya Aqurate is a modular set of products that offer
alternatives to any packaging grades that contain a white ply
through coating directly onto the brown or grey fiber plies. With
Omya Aqurate, manufacturers can substitute white fibers completely
with a coating.
Omya Aqurate products are not only focused on the board
manufacturer because they perform well in other parameters beyond
just excellent coverage and brightness. Omya Aqurate coated
substrates also provide a solution to various challenges in the
downstream printing and converting processes. Take for example
Omya Aqurate HA25, a type of ground calcium carbonate (GCC)
pigment that stands out with instant ink absorption. In this case,
the Aqurate coated linerboard will work ideally when printed on a
FlexoFolderGluer. These sheet-fed printing assets are still the vast
majority of the machines installed for printing onto corrugated board.
For Flexographic Inline postprint technology the biggest challenge
is typically the lack of an intermediate drying step after each printing
station. Even though most print jobs have only 2 or 3 colors, the
board surfaces need to manage the incoming ink freight without
compromising quality (ink smearing) or machine speed. Omya
Aqurate HA25 is not the only Aqurate pigment that converts well, all
pigments in the product family were designed and tested to allow for
seamless converting increasing, folding, gluing, etc.
There is another side of printing on the packaging board
where photorealistic designs are printed in high resolution.
Renderings of lively color gradients, gentle skin tones, or
homogeneous dark color full-tone areas are required. Ambitious
prints like this are enabled by new generations of flexo printing
machines like High-Quality Flexo Postprint (HQPP) and
Flexographic Preprint. Typical substrates used for these printing
jobs are Coated White Topliner (CWTL), Solid Bleached Sulfate
(SBS), or Coated Bleached Kraft (CUK). The correct substrate
is required to take full advantage of the excellent capabilities of
these new, top-notch, printing machines and meet premium quality
demands without compromising possible machine speed. Omya
Aqurate HD30 top-coat pigments deliver precise and vivid highcolor reproduction at high printing speeds because of their fast ink
absorption.
While the performance of Omya Aqurate pigments in printing
and converting is strong, the value of this product family is not
only limited to these process steps. Taking a holistic view, with an
Omya Aqurate-based coating replacing white fibers, a new space is
opened up for different aspects of packaging board. Light-weighting,
or said better, right-weighting of packaging can be realized by taking
the Omya Aqurate approach. A typical WTL, substance 140 gsqm,
has a white fiber ply of 35 gsqm and a target brightness of 73%
(TAPPI). Based on proven cases, the white fibers can easily be
substituted with a coating layer of approximately 15gsqm with Omya
Aqurate HA pigments, achieving the same brightness, homogenous
coverage, and identical converting results. The 20 gsqm saved by
the difference between 35 gsqm of white fibers versus 15gsqm of
coating, can now be allocated to a certain extent to the brown fiber
ply to fulfill the mechanical requirements in SCT, Bursting Strength.
When right-weighting board manufacturers can choose to use the
Omya Aqurate approach to reduce the total weight of their board
and reduce the Carbon Footprint of packaging by replacing precious
white fibers and optimizing grammage.
81