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Transcript of 1 Raising the Bar in Flexo High quality imaging High consistency imaging Raising the Bar in Flexo...
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Raising the Bar in Flexo
High quality imaging
High consistency imaging
Raising the Bar in Flexo
High quality imaging
High consistency imaging
FPPA Sanibel FL
February 2010
FPPA Sanibel FL
February 2010
Ian HoleV P Market DevelopmentEskoArtwork
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1HD 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 !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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● 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%
HighRes Optics: 4000ppi - finer screen dots
data transfer
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● Linework, Barcodes and Type are imaged more finely on plate
– So it prints cleaner, especially for smaller text
HighRes Optics: 4000ppi - improved linework
data transfer
4pt text - 2540ppi 4pt text - 4000ppi
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● 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
HD Screens – The best of several worlds
data transfer
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0,5% in CT prints with only 2% density.No need anymore to bump up CTNo loss of image contrastPre-press is simpler and quicker – no file conversion
“HD Flexo” achieves a full tonal range – 0% to 100%
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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
● 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 Flexo
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HD Flexo: better dot formation
Offset Flexo
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HD Flexo: better ink transfer than offset
Offset Flexo
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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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2Inline UV
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UV exposure of Screened dots
Inline UVInline UV Conventional Point Light UVConventional Point Light UV Conventional Bank UVConventional Bank UV
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UV exposure of shadows and reversed images
Inline UVInline UV Conventional Point Light UVConventional Point Light UV Conventional Bank UVConventional Bank UV
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• No UV degradation over time (year, month, week or day)
• Expected Lifetime = 5000h
Digital UV results in perfectly controlled plate production
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0 1250 2500 3750 5000 h
mW/cm²
Plate adjustable Digital UV level
Lifetime of Banklight vs Inline UV
• 30% UV light degradation over 1000h
• Degradation is manually compensated
Unstable plate quality production
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0 250 500 750 1000 h
mW/cm²
Lifetime extension by increasing exposure time
Typical lamp exchange
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mm0
200
400
600
800
1000
1200
0 500 1000 1500 2000
mm
Simultaneous movement of the UV source over the plate
Each cm² receives exactly the same light quality and quantity
• Uniform dot shaping throughout the whole plate
• Cool light – no heat distribution to plate or sleeve
Resulting in a predictable and consistent plate quality production
0
200
400
600
800
1000
1200
0 500 1000 1500 2000mm
mm
∆ =10%
Energy Emmission from lamp to lamp
• Intensity variations due to individual lamp aging
• Quality of light emission is varying from lamp to lamp
Resulting in an unstable plate quality production
Plate Surface exposure of Banklight vs Inline UV
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● 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.
Inline UV – Forward Step - Consistency & Automation
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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 saves an UV-Exposer device
Inline UV Main Exposure for Sleeves
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Banklight vs Inline UV
• 30% UV light degradation over 1000h
(each individual lamp)
• At least 1corrective intervention to compensate degradation
Resulting in an unstable plate quality production
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14
15
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18
19
20
0 250 500 750 1000h
mW/cm²
Lifetime extension by increasing exposure time
Typical lamp exchange
Lifetime
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14
15
16
17
18
19
20
0 1250 2500 3750 5000h
mW/cm²
Plate adjustable Digital UV level
• No UV degradation over time (year, month, week or day)
• Expected Lifetime = over 5000h
Digital UV results in perfectly controlled plate production
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Conventional Banklight UV Plate Surface
0
200
400
600
800
1000
1200
0 500 1000 1500 2000mm
mm
∆ =10%
Energy Emmission from lamp to lamp
• Uneven light emission over the plate due to individual lamp aging
• Quality of light emission is varying from lamp to lamp
Resulting in an unstable plate quality production
• Uniform dot shaping throughout the whole plate
• Cool light – no heat distribution to plate or sleeve
Resulting in a predictable and consistent plate quality production
mm0
200
400
600
800
1000
1200
0 500 1000 1500 2000
mm
Simultaneous movement of the UV source over the plate
Each sq.inch receives exactly the same light quality and quantity
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