GRAVURE vs.
HIGH QUALITY TONE FLEXO
There are many misconceptions about the relative costs of
rotogravure vs. flexography. For instance:
Rotogravure many years ago obtained a reputation for being
a high cost process from the publication industry. The process
was first used in publication and the nature of that business
was usually a one-shot run. Therefore, rotogravure printing
with its higher first-time cost had to be justified over a
longer run, hence the adage:
"Rotogravure is a process for long runs"
Unlike publication printing, packaging normally consists
of multiple production runs. (A very small volume of packaging
work today is a one-run situation).
This is a very significant point, when comparing pre-press
costs. In the case of flexo, there are pre-press costs associated
with each run, as the following examples will show. In the
case of rotogravure there is a pre-press cost for the first
run, and then no cost associated with each successive re-run.
The length of each run is relatively immaterial in the comparison,
but the fact that after a relatively few successive re-runs
rotogravure pre-press actually becomes lower in cost than
flexo when considering this amortized over the life of the
job.
Another factor concerning rotogravure, because of it's digital
nature and the fact that almost all roto cylinders today are
made using the electro-mechanical system, where a diamond
stylus produces each cell; the scale of cost increase from
very basic line work, or text, up to fine process tone work;
is minimal. The cost of a roto engraving is essentially based
on size and area, more so than difficulty.
This is not so true with flexo, where there is a much broader
range of difficulty and hence costs involved, going from basic
print, to high quality process work. The scale in plate cost
alone can range five-times considering a rubber plate up to
a high-end photo polymer.
Finally, another basic difference in flexo vs. roto printing
is that rotogravure is a process that inherently can print
both solids and process tones within the same image carrier.
Flexo, Litho and Letterpress, because of their different ink
delivery systems employed, cannot usually do this without
severe compromise in quality.
For instance, if it is needed to print three colors, red,
yellow, and blue in process and also the same colors in solid
within the copy; rotogravure could easily do this in (3) stations.
The latter processes would probably require six stations!
The following study uses data obtained from several trade
houses that specialize in roto and flexo plate making as well
as information obtained from printers that do their own flexo
pre-press. It attempts to illustrate by practical example
the cost differences that can be anticipated when considering
a narrow-web press situation doing high-end tone printing.sidering
this amortized over the life of the job.
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