Transcript Flexo Academy

Raising the Bar in Flexo
High quality imaging
High consistency imaging
FPPA Sanibel FL
February 2010
Ian Hole
V P Market Development
EskoArtwork
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HD Flexo
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Prepress for Flexo still has some limitations
● Digital CTP (EskoArtwork CDI 75% worldwide) has made big improvements
in Consistency, Productivity and Quality
● BUT the tonal range is still limiting
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Flexo can have a reduced tonal range
● The minimal printable dot in the
highlights causes:
●
Tonal Jump
●
Color shift
●
Loss of detail
Reduced Tonal Range !
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So this has limited some applications for Flexo
● Some designs are very hard to print – still printed Offset or Gravure
● Manual adjustment of CT images needed – Bump Curves
– To increase size of non-printable dots – this causes loss of contrast
● Intensive pre-press work sometimes needed
– Different screening needed per object OR
– Splitting jobs into different plates for line and CT’s
● All this increases the complexity
● Increases the cost
● And still limits the quality…
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Introducing HD Flexo – What is it?
● A new product for 2009 from EskoArtwork
● It revolutionizes digital flexo by offering digital imaging that is
both high quality and still easy to use
● It was developed from strong existing know-how
– 4000ppi Optics – existed since before 2000
– HD Screening Technology – new screening software combination
● HD Flexo is available as a field retrofit for most existing CDI’s and
an option on all new machines
– Retaining all Digital Workflow advantages
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HighRes Optics: 4000ppi - finer screen dots
● 3x more data to describe the same dot shape
● Dots are more round and dot shoulders are perfectly shaped
● Rounder shape means less Dot Gain
● 4000ppi means dots can be smaller  highlights
● Extended tonal range 0 to 100%
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data transfer
HighRes Optics: 4000ppi - improved linework
● Linework, Barcodes and Type are imaged more finely on plate
– So it prints cleaner, especially for smaller text
4pt text - 2540ppi
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data transfer
4pt text - 4000ppi
HD Screens – The best of several worlds
● A combination of several EskoArtwork screens using the best from each –
AM regular pattern, Variable dot sizes, Support dots and Curve choices
● AM dots means the are no isolated dots that can be unsupported
● Variable Dot sizes in highlights  better gradation to zero
● Variable dot range means that dots reach zero at different points in the
gradation – no hard edge
● Plates last longer on print run
● Fewer cleaning cycles are needed on press
● So there is more press uptime (cost saving) and a more stable print
process
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data transfer
“HD Flexo” achieves a full tonal range – 0% to 100%
0,5% in CT prints with only 2% density.
No need anymore to bump up CT
No loss of image contrast
Pre-press is simpler and quicker – no file conversion
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HD Flexo: A Case Study
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Who are Rako Etiketten?
● Label converter headquartered in Germany
– - one of largest producers of self adhesive labels in Europe
● 500+ staff, 34 presses, 18 sites
● Use all print processes
– Offset, Flexo, Letterpress, Screen, Digital
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Motivation for HD Flexo?
● For - Increased print quality
– Sharper text and line art
– Increased rulings 150 – 200 LPI
– Vignettes down to “substrate” zero
● To - Move jobs from Offset to Flexo
– Flexo printing presses are less expensive (capital equipment cost) than
offset (3x)
– Wastage during startup (to get color OK) is lower for flexo than offset
● 100 feet – 15 feet
– Ink transfer for many label substrates is better with flexo
● increased quality and more versatile
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What stopped moving jobs to Flexo before?
● Quality expectations could not be met before
– Limitations on screen ruling
– Minimum dot in Flexo to big
● Prepress cost (and time) was greater for Flexo
– Jobs required manual file conversion
– High prepress costs are more than costs of printing Offset
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Typical production job
● Adhesive label - beauty products
● Design mainly line art, but contains a soft
gradation
– Gradation critical for standard Flexo
– Gradation critical to Dove the customer
– Labels and Cartons printed Offset normally
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Experience with HD Flexo trials
● Customer printed the same
job both Offset and HD Flexo
● Both sets of plates from the
same digital file
● HD Flexo met customer
expectations
– Quality of HD Flexo was
actually better than Offset
– See following slides for some
micrographs and technical
details
Offset
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Flexo
HD Flexo: better dot formation
Offset
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Flexo
HD Flexo: better ink transfer than offset
Offset
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Flexo
Tonal curve of print sample
Tone curve of HD Flexo in highlights is close to linear. 1% printable
minimum dot
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Tone curve - highlight region
● Close-up of the highlight shows the excellent min dot behavior of HD Flexo
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Inline UV
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UV exposure of Screened dots
Inline UV
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Conventional Point Light UV
Conventional Bank UV
UV exposure of shadows and reversed images
Inline UV
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Conventional Point Light UV
Conventional Bank UV
Lifetime of Banklight vs Inline UV
mW/cm²
cm²
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Lifetime extension by increasing
exposure time
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Plate adjustable Digital UV level
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Typical lamp
exchange
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0
250
1250
500
2500
750
3750
1000hh
5000
No UVUV
degradation
over time
(year,
month, week or day)
• 30%
light degradation
over
1000h
Expected Lifetime
= 5000h
• Degradation
is manually
compensated
Digital UV plate
resultsquality
in perfectly
controlled plate production
Unstable
production
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Plate Surface exposure of Banklight vs Inline UV
mm
mm
1200
Simultaneous movement of the UV
source over the plate
1000
800
Each cm² receives exactly the same
light quality and quantity
600
400
∆ =10%
200
Energy Emmission from lamp to lamp
0
mm
0
500
1000
1500
2000
• Intensity
Uniform dot
variations
shapingdue
throughout
to individual
the whole
lamp aging
plate
• Quality
Cool light
of –
light
no heat
emission
distribution
is varying
to plate
from lamp
or sleeve
to lamp
Resulting
Resulting
in in
a predictable
an unstable and
plate
consistent
quality production
plate quality production
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Inline UV – Forward Step - Consistency & Automation
● Consistency and Repeatability leading to Automation
EskoArtwork UV technology converts the UV Main Exposure from an
uncontrollable analog process to a high precision digital process.
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Inline UV - Summary
● Predictable plate quality over years
● Reduced plate wastage
● No Press Down time
● Maintenance Free
Markets
● Mid to Wide Web Flexible Pkg
● High Quality Labels
● High quality Corrugated
● Solvent, Thermal, Water wash
● Sleeves
– No back-exposure
● LetterPress metal backed plates
– No back-exposure
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Inline UV Main Exposure for Sleeves
Inline UV Main Exposure for sleeves saves an UV-Exposer device
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Banklight vs Inline UV
Lifetime
mW/cm²
mW/cm²
20
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Lifetime extension by
increasing exposure time
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16
16
15
15
Typical lamp
exchange
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Plate adjustable Digital UV level
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13
0
250
500
• 30% UV light degradation
750
over 1000h
(each individual lamp)
• At least 1corrective intervention to
1000 h
0
1250
2500
3750
5000 h
•
No UV degradation over time (year, month,
week or day)
• Expected Lifetime = over 5000h
compensate degradation
Resulting in an unstable plate quality
production
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Digital UV results in perfectly controlled
plate production
Conventional Banklight UV
Plate Surface
mm
mm
1200
1200
1000
1000
800
800
600
600
400
0
30
200
Energy Emmission from lamp to lamp
0
500
1000
1500
Each sq.inch receives exactly the
same light quality and quantity
400
∆ =10%
200
Simultaneous movement of the
UV source over the plate
mm
2000
0
0
500
1000
1500
mm
2000
•
Uneven light emission over the plate due to
individual lamp aging
• Uniform dot shaping
• Quality
of light emission is varying from
lamp to lamp
• Cool light – no heat distribution
Resulting in an unstable plate quality
production
Resulting in a predictable and consistent
plate quality production
plate
sleeve
throughout the whole
to plate or
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