printing as a means of paper testing
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Printing as a Means of Paper TestingPetter Kolseth
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 2
The structure of paperInk on matt-coated fine paper
Ink film thickness of 1-2 µm on ~15 µm coating
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 3
Ink film thickness on coated fine paper
Silk
Matt
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 4
Runnability in sheet-fed offsetFull-scale trial on low-grammage coated
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 5
Different types of print
• Newspapers• Magazines• Special interest magazines• Manuals• Books• Art books, coffee table prints• Corporate communication, Annual reports• Sales promotion• Direct mail
• Paper testing
Reproduction of text and images to please the reader, advertiser or artist
ExpectationsTotal impressionPrint quality
Reproduction of technical areas that reveal the potential of the paper
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 6
• Print mottle– back-trap, water-induced, halftone, gloss
• Colour gamut• Tone Value Increase• Print evenness
– Potential to carry dark and heavily inked images• Ink drying and ink setting• Trapping values
What should we include in print quality potential?
Today’s presentation
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 7
• Full-scale print trials– Lab prints are not enough
• Controlled print run– Target densities– Standard settings (impression, speed…)– Controlled climate– Standard supplies (inks, plates, blankets…)
• Calibrated press– Ink roller settings– Fount roller settings (use FOGRA’s test form!)
• Dedicated print layout– Technical areas– No images
How to determine print quality potential?
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 8
Sheet offset on coated woodfreeStandardised Print
• Market follow-up on 50 European papers– Paper Type 1 and 2
• Comparison of 10 inks on three papers – Gloss, silk, matt (Type 1 and 2)
Scanning densitometer Print layoutGretag Spectrolino
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 9
A print layout for print quality potential: K-C-M-Y-C
Print Mottle
No back-trapInk SettingTone Curves
2nd unit No back-trap
5th unitNo back-trap
Print Evenness
C50 + M50 C80C + M40M
CMY
RGB
400 KK40
Ink setting and drying
2nd unit
K40
C100Print gloss 400%Ink scuffing
Print gloss Black
C100
C100 K40
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 10
Different types of mottled print
• Back-trap mottle– Uneven ink films and transparent inks
• Water-induced mottle– Uneven ink transfer– Ink refusal where excess fount can’t be accommodated in coating
• Paper optics– Halftone mottle – Yule-Nielsen effects in screen tones– Gloss mottle
• Ink trap mottle– Uneven trapping of second ink
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 11
Print Mottle
Solid Cyan Blue halftones C+M 40% black
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 12
What is back trap?
• ’Trapping’ is when ink is transferred to a wet ink film on the paper– (e.g. magenta on cyan)
• Back trap is when the wet ink is transferred from the paper to the following blanket
– (e.g. cyan onto magenta blanket)
• Ideally, an equilibrium ink-film thickness is formed on back-trap blankets
• Subsequent ink-film splits in back trap level out the unevenness formedby collapsing ink filaments(higher print density in black after back trap)
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 13
Four-colour offset printing
Black inkBlanket to paper
Cyan inkBlanket to paper
Black inkPaper to blanket
Magenta inkBlanket to paper
Black inkPaper to blanket
Cyan inkPaper to blanket
Yellow inkBlanket to paper
Black inkPaper to blanket
Cyan inkPaper to blanket
Magenta inkPaper to blanket
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 14
Five-cylinder configuration with chain transfer systems
M2,5 s
KC0,25 s
Y0,25 s
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 15
Back-trap equilibrium is more easily disturbed for the first inks down
1,00
1,20
1,40
1,60
1,80
2,00
Printing order
Prin
t den
sity
equilibrium equilibriumequilibrium
paper with slow
ink settingchange to paper with
medium ink-setting rateback to paper with
slow ink setting
paper with slowink setting
paper with medium ink-setting rate
paper with slowink setting
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 16
Immobilisation of a setting ink film
0,1 s 1 s 3 s 10 s 30 s 1 min 3 minInk setting time
immobilisation front moves upwards through ink film
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 17
Shift of ink split position after changing to a faster setting paper
non-immobilized inkimmobilized inkpaper coating
back-trap ink on last blanket 50%
50%
splitting of non-immobilized ink film
non-immobilized inkimmobilized inkpaper coating
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 18
The effect is highly dependent on ink-setting rate
1,00
1,20
1,40
1,60
1,80
2,00
2,20
Printing order
Prin
t den
sity
equilibrium equilibriumequilibrium
paper with slow
ink settingchange to paper with fast ink-setting rate
back to paper with slow ink setting
paper with slowink setting
paper with fast ink-setting rate
paper with slowink setting
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 19
Print on sheet with uneven ink-setting characteristics
sheet with ”slow-setting spots” gets mottled after back-trap
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 20
The memory effect Uneven print also on next sheet
”spotless” sheet gets mottled print due to back-trap
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 21
Water-induced print mottle
• Printing on pilot-coated paper
• Low coating porosity resulting in unwanted hold-out of fount
• Excessive feed of fount in all print units
• Ink refusal where coated surface was too wet
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 22
Increasing the fount supply results in white spots in the solid print
low fount supply high fount supply
Solid areas printed without pre-damp but with back-trap(10 pts SB-latex)
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 23
Back-trap will improve print quality in areas with excessive pre-damp
no back-trap with back-trap
70% areas printed with pre-damp(15 pts PVAc-latex)
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 24
Excessive pre-damp may ruin print quality of high binder content coatings
no pre-damp with pre-damp
70% areas printed with back-trap(20 pts SB-latex)
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 25
Disturbed ink transfer after excessive fount supply in four printing units
2nd unit 5th unit
burnoutGloss-coated 250 gsm
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 26
Disturbed ink transfer after excessive fount supply in four printing units
2nd unit 5th unit
burnoutSilk-coated 250 gsm
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 27
Mottle in black screen tones
• High contrast between black dots and surrounding white paper
• Total reflectance is average of unprinted white and (non-reflecting) black dots
• Ink film density not very important
• Yule-Nielsen shadows in white areas is a major contribution
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 28
Optical dot gainYule-Nielsen shadows
Stefan Gustavson, LiU 1998
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 29
Optical dot gainEffect on tone value and colour
after Matthieu Bossan, Creo, 2002
AM
FM
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 30
Optical dot gainYule-Nielsen shadows
coating
base sheet
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 31
Optical dot gainYule-Nielsen shadows
Lost light ray due to lateral light scattering in base sheet
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 32
Halftone mottle correlates to coat weight variations
Coat-weight variations (burnout test)
Print mottle in 40% black
0.0 2.5 5.0 7.51.0
1.2
1.4
1.6
1.8
2.0
Further evidence:SEM images show that
Dark regions have thin coating(more Yule-Nielsen shadow from base paper)
No significant difference in physical(mechanical) tone between dark and light regions
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 33
Burn out – Coat weight variations
Halftone mottle = 1,51Coat weight = 18 gsm
Halftone mottle = 0,94Coat weight = 22 gsm
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 34
Ink-trap mottle and more…Blue halftones (Cyan+Magenta)
• Blue halftones combine ink-trap mottle and the two basic types of mottle:
– the halftone character showing dot gain variation
– the transparent ink film showing ink film thickness variation
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 35
Print evenness is important in heavy images
864200
2
4
6
8
10
Print evenness
Quality index, Fruit
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 36
Print evennessGloss mottle – Print gloss homogeneity
Mikael Lindstrand, STFI
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 37
Print evennessthree different surfaces on a curved sample holder
Mikael Lindstrand, STFI
plastic film good WFC poor LWC
1 mm
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 38
Print evenness – Surface roughness
1
2
3
4
5
0,40 0,60 0,80 1,00 1,20 1,40
Surface roughness
Prin
t eve
nnes
s
Gloss-Coated 200 – 350 gsm
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 39
Print evenness – Paper gloss
Gloss-Coated 200 – 350 gsm
1
2
3
4
5
55 60 65 70 75 80 85
Paper gloss
Prin
t eve
nnes
s
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 40
Print evenness – Print gloss 400
Gloss-Coated 200 – 350 gsm
1
2
3
4
5
75 80 85 90 95
Print gloss 400%
Prin
t eve
nnes
s
Paper shadeLudovic Coppel, Innventia
Paper shade
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 42
Print substrate colour and glossISO 12647-2: Offset lithography
• Five typical paper types and their shade/colour and gloss: Paper type L* a* b* gloss1. Gloss-coated, woodfree 93(95) 0(0) -3(-2) 652. Matte-coated, woodfree 92(94) 0(0) -3(-2) 383. Gloss-coated, web 87(92) -1(0) 3(5) 554. Uncoated, white 92(95) 0(0) -3(-2) 65. Uncoated, slightly yellowish 88(90) 0(0) 6(9) 6Tolerance ±3 ±2 ±2 ±5----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
– Black backing to allow for showthrough from reverse printValues in brackets refer to white backingSubstrate backing (white) is standard in paper industry
– D50 illuminant, 2° observer, 0/45 or 45/0 geometryD65/10° or C/2° and d/0° geometry is standard in paper industry
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 43
Print substrate used for proofingISO 12647-2: Offset lithography
• Five typical paper types and their shade/colour and gloss: Paper type L* a* b* gloss1. Gloss-coated, woodfree 93(95) 0(0) -3(-2) 652. Matte-coated, woodfree 92(94) 0(0) -3(-2) 383. Gloss-coated, web 87(92) -1(0) 3(5) 554. Uncoated, white 92(95) 0(0) -3(-2) 65. Uncoated, slightly yellowish 88(90) 0(0) 6(9) 6Tolerance ±3 ±2 ±2 ±5----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
• Print substrate used for proofing – identical to that of the production• If not possible – close match in colour, gloss, surface grammage• Press proofing on closest match to five typical paper surface types • Proof substrate to conform … to attributes in Table 1 of the paper type
representing the production paper
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 44
-10
-9
-8
-7
-6
-5
-4
-3
-2
-1
0
-5 -4 -3 -2 -1 0 1 2 3 4 5
CIELAB-a*
CIE
LAB
-b*
Paper shade – Elrepho D65/10°Paper Type 1 – 90-250 gsm
Measurements according to paper industry standard
All products out-of-range
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 45
-10
-9
-8
-7
-6
-5
-4
-3
-2
-1
0
-5 -4 -3 -2 -1 0 1 2 3 4 5
CIELAB-a*
CIE
LAB
-b*
Paper shade – Elrepho D65/10°Paper Type 2 – 90-250 gsm
Measurements according to paper industry standard
All except one products out-of-range
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 46
Paper shade – Elrepho C/2°Paper Type 1 – gloss 90-250 gsm
Measurements according to "indoor whiteness" standard
Some products in the box
-10
-9
-8
-7
-6
-5
-4
-3
-2
-1
0
-5 -4 -3 -2 -1 0 1 2 3 4 5
CIELAB-a*
CIE
LAB
-b*
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 47
-10
-9
-8
-7
-6
-5
-4
-3
-2
-1
0
-5 -4 -3 -2 -1 0 1 2 3 4 5
CIELAB-a*
CIE
LAB
-b*
Paper shade – Spectrolino D50/2°Paper Type 1 – 90-250 gsm
Measurements according to printing industry standard
UV content not known
Most products in the box
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 48
Paper shade – D65/10° - D50/2° - i1 D50/2°Paper Type 2 – Silk-coated fine paper
-20
-15
-10
-5
0
5
10
15
20
-20 -15 -10 -5 0 5 10 15 20
a*
b*
D50 i1D50 D65
Moderate fluorescence
The D65 UV setting high enough to offset the b*
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 49
Paper shade – D65/10° - D50/2° - i1 D50/2°Paper Type 3 – Uncoated fine paper
-20
-15
-10
-5
0
5
10
15
20
-20 -15 -10 -5 0 5 10 15 20
a*
b*
D50 i1D50 D65
Strong fluorescence
The D65 UV setting gives even larger offset in b*
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 50
Paper shade – D65/10° - D50/2° - i1 D50/2°Paper Type 4 – Uncoated WoodFree without OBA
-20
-15
-10
-5
0
5
10
15
20
-20 -15 -10 -5 0 5 10 15 20
a*
b*
D50 i1D50 D65
No fluorescence
D65 and D50 quite close, but D50 slightly more red
Conclusions – Paper Shade
A matter of taste – forget "ISO compliant"
ISO does not specify allowed shades
Should be determined with dedicated equipment
Most papers are within a narrow range of shades
Primaries and SecondariesAndreas Paul, FOGRA
Primaries and Secondaries
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 53
Colour gamut – Spectrolino D50/2°Paper Type 1 and 2, gloss/matt/silk 90-250
-100
-80
-60
-40
-20
0
20
40
60
80
100
-100 -80 -60 -40 -20 0 20 40 60 80 100
a*-a*
-b*
b*GlossMatt/Silk
Target valuesAll prints rather close to target colour CMYRGBOriginal RGB targets
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 54
Colour gamut – Spectrolino D50/2°Paper Type 1 and 2, gloss/matt/silk 90-250
-100
-80
-60
-40
-20
0
20
40
60
80
100
-100 -80 -60 -40 -20 0 20 40 60 80 100
a*-a*
-b*
b*All prints very close to target colour CMYRGBAfter the 2004 Amendment
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 55
Ten inks on gloss, silk and matt paperColour gamut – Elrepho C/2°
-100
-80
-60
-40
-20
0
20
40
60
80
100
-100 -80 -60 -40 -20 0 20 40 60 80 100
CIE a*CIE -a*
CIE b*
CIE -b*
Ten inks on Gloss paperTen inks on Silk paperTen inks on Matt paper 30 ink-paper
combinations but almost identical results
Conclusions – Primaries and Secondaries
No (or very small) influence of paper brand
Target colours can be reached with standard inks
Paper fluorescenceLudovic Coppel, Innventia
Paper fluorescence
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 58
Fluorescence – CIE Whiteness (D65)
Gloss-Coated 200 – 350 gsm
10
20
30
40
50
60
70
100 110 120 130 140 150
CIE Whiteness (D65/10°)
Fluo
resc
ence
(D65
/10°
)
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 59
CIE Whiteness – CIELAB-b* (D65)
Gloss-Coated 200 – 350 gsm
100
110
120
130
140
150
-14 -12 -10 -8 -6 -4 -2 0
CIELAB-b* (D65/10°)
CIE
Whi
tene
ss (D
65/1
0°)
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 60
Primaries and Secondaries – Elrepho D65/10°Paper Type 2 – Silk-coated fine paper
-60
-40
-20
0
20
40
60
80
100
-80 -60 -40 -20 0 20 40 60 80
a*
b*
Elrepho D65/10°
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 61
Primaries and Secondaries – i1 D50/2°Paper Type 2 – Silk-coated fine paper
-60
-40
-20
0
20
40
60
80
100
-80 -60 -40 -20 0 20 40 60 80
a*
b*
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 62
Primaries and Secondaries – D50/2°Paper Type 2 – Silk-coated fine paper
-60
-40
-20
0
20
40
60
80
100
-80 -60 -40 -20 0 20 40 60 80
a*
b*
Elrepho D50/2°
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 63
Primaries and Secondaries – D50/2° UV excludedPaper Type 2 – Silk-coated fine paper
-60
-40
-20
0
20
40
60
80
100
-80 -60 -40 -20 0 20 40 60 80
a*
b*
Elrepho D50/2° UV excluded
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 64
Spectral power and Relative UV contentIlluminants D65, C, D50, A
0
50
100
150
200
250
300
350 400 450 500 550 600 650 700 750
Wavelength, nm
Spec
tral P
ower
D65 C D50 A
Relative to 560 nm (max colour vision)
0,00
0,25
0,50
0,75
1,00
1,25
1,50
1,75
2,00
340 360 380 400 420 440 460 480 500 520 540 560
Wavelength, nmSp
ectra
l Pow
er
D65rel Crel D50rel Arel
Relative to 440 nm fluorescence peak
Relative power of A is almost twice that of C between 340 and 380 nm
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 65
Illumination is NOT same as Illuminant Illumination 5000K and Illuminant D50
Ludovic Coppel, Innventia, 2008300 350 400 450 500 550 600 650 700 7500
0,5
1
1,5
2
Wavelength (nm)
Rel
ativ
e Po
wer
D50D655000K CCT5000K CCT + UV
300 350 400 450 500 550 600 650 700 7500
0,5
1
1,5
2
Wavelength (nm)
Rel
ativ
e Po
wer
D50D655000K CCT5000K CCT + UV
D50D655000K CCT5000K CCT + UV
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 66
-14,0
-12,0
-10,0
-8,0
-6,0
-4,0
-2,0
0,0
2,0
4,0
6,0
-2,0 -1,5 -1,0 -0,5 0,0 0,5 1,0 1,5 2,0 2,5 3,0
CIELAB-a*
CIE
LAB
-b*
Proof substrates from one supplierx-rite iOne – a*-b* data
Red symbols denote certified proof substrates
Green symbols denote production paper PT2 and PT4
Type 2
Type 4
Conclusions – Paper Fluorescence
Fluorescence make papers whiter (more blue)
Effect is very dependent on illumination
Fluorescence shines through all print
Matching proof to print with proper choice of proof substrate and illumination
Tone Value Increase
Tone Value Increase
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 69
Tone Value Increase: Black and CyanPaper Type 1 – 90-250 gsm
Black and Cyan Dot Gain are both within tolerance
0%
5%
10%
15%
20%
25%
30%
0% 20% 40% 60% 80% 100%
Nominal tone
Bla
ck T
one
Valu
e In
crea
se
20% +/- 4
0%
5%
10%
15%
20%
25%
30%
0% 20% 40% 60% 80% 100%
Nominal tone
Cya
n To
ne V
alue
Incr
ease
20% +/- 4
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 70
Optical dot gainEffect on tone value and colour
after Matthieu Bossan, Creo, 2002
AM
FM
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 71
Reflectance histograms of K100, K40 and paper white13,2% TVI(40)
0,0
0,5
1,0
1,5
2,0
2,5
0 20 40 60 80 100
Reflectance, %
Freq
uenc
y, %
0,0
5,0
10,0
15,0
20,0
25,0
<K40> <BLACK> <WHITE>
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 72
Reflectance histograms of K100, K40 and paper white20,1% TVI(40)
0,0
0,5
1,0
1,5
2,0
2,5
0 20 40 60 80 100
Reflectance, %
Freq
uenc
y, %
0,0
5,0
10,0
15,0
20,0
25,0
<K40> <BLACK> <WHITE>
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 73
0,0
0,5
1,0
1,5
2,0
2,5
0 20 40 60 80 100
Reflectance, %
Freq
uenc
y, %
0,0
5,0
10,0
15,0
20,0
25,0
<K40> <BLACK> <WHITE>
Reflectance histograms of K100, K40 and paper white13,2% TVI(40)
Solid black
Halftone dots Between dots
Unimaged paper
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 74
0,0
0,5
1,0
1,5
2,0
2,5
0 20 40 60 80 100
Reflectance, %
Freq
uenc
y, %
0,0
5,0
10,0
15,0
20,0
25,0
<K40> <BLACK> <WHITE>
Reflectance histograms of K100, K40 and paper white20,1% TVI(40)
Solid black
Halftone dots
Between dots
Unimaged paper
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 75
Black halftone seen in the microscope
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 76
Thresholding between peaks in histogram
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 77
Tone Value comparisonDensitometer readings vs. microscopy
46
48
50
52
54
56
50 52 54 56 58 60 62 64
Densitometer Tone Value
Mic
rosc
opy
Tone
Val
ue
28 Octoberl 2009 Printing for Paper Testing / Petter Kolseth 78
0,0
2,0
4,0
6,0
8,0
10,0
-20 -15 -10 -5 0
Reduction in paper reflectance between dots
Opt
ical
TVI
Optical Tone Value Increase Tone Values by microscopy
Single-coat matt
multicoat gloss multicoat silk
Conclusions – Tone Value Increase
Mechanical TVI is small (in the ideal case)
Optical TVI is quite large
Optical TVI is an inherent paper property (but not related to brand)
TVI variations are mechanical due to press settings
Stay in control…
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