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Publication Gravure
Publication gravure is used primarily for very long press runs required
to print mass-circulation periodicals, directories, inserts, and catalogs.
Publication gravure maintains a competitive edge in the printing of
mass-circulation magazines because the process offers high speed, high
quality four color illustrations on less expensive paper, variable cut-off
lengths, and flexible folding equipment. These presses can have as many as
ten printing stations - four for color and one for monochrome text and
illustration in each direction so that both sides of the web can be
printed in one non-stop operation. They can handle web widths of up to 125
inches and are equipped to print most large format publications in
circulation today. Publication gravure presses can also be fitted with
cylinders of differing diameters to accommodate varying page sizes.
The major types of chemicals used in publication gravure include
adhesives, metal plating solutions, inks, and cleaning solvents. In terms
of chemicals, publication gravure differs from packaging and product
gravure primarily in its heavy reliance on toluene-based ink (GATF 1992b).
The publication gravure industry has had little success with water-based
inks (Buonicore). The industry has found that in publication gravure where
the substrate is always paper stock, water-based inks have not been
capable of printing commercially acceptable quality productions runs of
2,000 to 3,000 feet per minute.
Packaging Gravure
Packaging rotogravure presses are used for printing folding cartons as
well as a variety of other flexible packaging materials. In addition to
printing, packaging gravure presses are equipped to fold, cut, and crease
paper boxes in a continuous process. Packages are usually printed on only
one side, so the number of print stations is usually about half that
required for publication gravure presses. However, in addition to printing
stations for the four basic colors, packaging gravure presses may employ
printing stations for the application of metallic inks and varnishes as
well as laminating stations designed to apply foils to the paper substrate
prior to printing.
Packaging gravure presses are designed with the accurate cutting and
creasing needs of the packaging material in mind. However, image quality
is generally less important in packaging printing than in most other types
of printing and, subsequently, receives less emphasis.
The chemicals used in packaging gravure are similar to those used in
publication gravure. However, the inks used in packaging gravure are
largely alcohol- and not toluene-based (GATF 1992b). Water-based inks are
being successfully used for lower quality, non-process printing on paper
and paperboard packaging and for printing on non-absorbent packaging
substrates such as plastics, aluminum, and laminates (Tyszka 1993). Use of
water-based inks is expected to increase; however, problems still limit
their use at press speeds above 1,000 feet per minute (Buonicore).
Product Gravure
The continuous printing surface found on gravure press cylinders
provides the "repeat" required to print the continuous patterns
found on textiles and a variety of other products. In the textile
industry, a gravure heat transfer process using subliming dyes is used to
print images on paper. These images are then transferred from the paper to
a fabric (usually polyester) through a combination of heat and pressure.
The gravure process is also used to print continuous patterns on
wallboard, wallpaper, floor coverings, and plastics.
The chemicals used in product gravure are similar to those used in both
publication and packaging gravure. However, product gravure uses both
water- and solvent-based inks (GATF 1992b). The industry has used
water-based inks successfully on medium-weight papers and on nonabsorbent
substrates such as plastics, aluminum, and laminates (Tyszka 1993).
However, problems such as paper distortion and curl persist with
lightweight papers (Buonicore).
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