introduction to silver digiplate technology

Transcription

Brief-Guide-2007_GB_2c.qxd
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Seite 1
INTRODUCTION TO
SILVER DIGIPLATE TECHNOLOGY
Computer-to-Plate
Application of Silver
Digiplate polyester and paper
printing plates
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Seite 2
CONTENTS
CONTENTS
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Product information: Silver Digiplate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
1.0
1.1
1.1.1
1.1.2
1.2
1.2.1
1.2.2
1.2.3
1.3
1.4
1.4.1
1.4.2
Output methods for Silver Digiplate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
Imagesetter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Output mode
Resolution
Calculating the optimum exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Laser intensity
Calibration
Ongoing checking
Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Punching, cutting, bending . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Punching
Bending polyester plates
2.0
2.1
2.2
2.2.1
2.2.2
2.2.3
2.3
2.3.1
2.3.2
2.3.3
Proofing-solutions and Color management for Silver Digiplate . . . . . . . 13
Application of the proofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Workflow profiling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Printing machine profiling
Proof printer profiling
Profiling principles
Usage of the ICC-Profiles on Mitsubishi SDP-RIP . . . . . . . . . . . . . . . . . . . . 14
Different color gamuts through Rendering Intents
Mitsubishi Proof-Colourdot – the simple way to the perfect proof
Inkjet-Proof materials from Mitsubishi HiTec Paper
3. 0
3.1
3.1.1
3.1.2
3.1.3
Printing with Silver Digiplate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Print settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Setting the press
Adjusting the dampening solution
Additional dosing units
4.0
4.1
4.2
4.3
Dampening solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Dampening Solution Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Additional Mitsubishi additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Dampening solution mixing plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.0
Inks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
6.0
6.1
6.2
Cleaning solution and print dusting powder . . . . . . . . . . . . . . . . . . . . . . 20
Cleaning solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Print dusting powder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
7.0
7.1
7.2
7.3
Starting up the press . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Combined dampening Systems (e.g. DAHLGREN, ALCOLOR) . . . . . . . . . 21
Separate dampening Systems (e.g. KOMORIMATIC) . . . . . . . . . . . . . . . . 21
Restarting the press . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
8.0
Recommendations for non-standard presses
. . . . . . . . . . . . . . . . . . . . . 22
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CONTENTS
INTRODUCTION
9.0
9.1
9.2
9.3
9.4
Plate clamping procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Plate cylinder backing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Plate clamping bars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Clamping the SDP plates on presses with no autoplate system . . . . . . . . 23
Clamping the SDP plate on presses wiht an autoplate system . . . . . . . . . 24
INTRODUCTION
10.0
Multi-colour printing with SDP plates,
taking the Heidelberg PM 46 /QM 46 as an example . . . . . . . . . . . . . . . .24
Basic machine settings and prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Clamping the plates with an autoplate system . . . . . . . . . . . . . . . . . . . . . 25
Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Register with polyester plates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
offset-plate technology based on the same
Four-colour printing with SDP plates,
taking the RYOBI 3304H as an example . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Basic machine settings and prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . 26
Optimising the register printing for Ryobi 3304 . . . . . . . . . . . . . . . . . . . . 26
imagesetter or other film imagesetter, without
10.1
10.2
10.3
10.4
11.0
11.1
11.2
12.0
12.1
12.2
12.3
12.4
12.5
13.0
13.1
14.0
14.1
15.0
15.1
16.0
16.1
16.2
16.3
16.4
16.5
16.6
16.7
16.8
16. 9
16.10
16.11
4
taking the Heidelberg SM 52 as an example . . . . . . . . . . . . . . . . . . . . . . . 27
Clamping the plates with an autoplate system . . . . . . . . . . . . . . . . . . . . . 27
Start-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Register with polyester plates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Optimize register printing for SM 52 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
taking the RYOBI 524H as an example . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
taking the Ryobi 784 as an example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Two- or four-colour printing with SDP plates,
taking the Heidelberg SM74 as an example . . . . . . . . . . . . . . . . . . . . . . . 30
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Exposure problems (at plate production) . . . . . . . . . . . . . . . . . . . . . . . . . 31
Faulty reproduction (causes associated with the processor) . . . . . . . . . . . 31
Faulty reproduction (other causes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Scumming problems (Prerequisite: well exposed printing plate) . . . . . . . 32
Inferior rendering in the printing process
(Prerequisite: well exposed printing plate) . . . . . . . . . . . . . . . . . . . . . . . . 32
Voids in printing area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Poor ink acceptance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Poor reproduction of screen ruling points . . . . . . . . . . . . . . . . . . . . . . . . . 34
Emulsification of ink . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Roller-stripping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Register alignment differences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Silver Digiplate (SDP) is an extremely advanced
principles as silver-halide photography; SDP plates
are exposed directly in a polyester plate
any intermediate processes.
Silver Digiplate is available in the form of polyester or paperbased plates.
Silver Digiplate is distinguished by its excellent workability despite the minimal process maintenance requirement. SDP is compatible with the majority of laser imagesetters and is ideal for use
with conventional offset presses.
This manual describes the characteristics of the Mitsubishi Silver
Digiplate and provides potential users with recommendations
for integrating this method into their existing plant.
This manual may not be duplicated or reproduced without the
prior permission of Mitsubishi Paper Mills Ltd.
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PRODUCT INFORMATION
OUTPUT METHODS
Product information: Silver Digiplate
Designation
Material
Material
thickness
Light source
Max. Print run
SDP-FRS175
Film
0.20 mm
Red-LD (633-680 nm)
He-Ne (633 nm)
20,000 sheets
SDP-FR100
Film
0.12 mm
Red-LD(633-680 nm)
He-Ne (633 nm)
20,000 sheets
SDP-RR 175
Paper
0.19 mm
Red-LD(633-680 nm)
He-Ne (633 nm)
10,000 sheets
SDP-FE175
Film
0.20 mm
LED (670-680 nm)
20,000 sheets
SDP-FD100/175
Film
0.12/0.20 mm
Infrared (780 nm)
20,000 sheets
SDP-RD175
Paper
0.19 mm
Infrared (780 nm)
10,000 sheets
1.0
OUTPUT METHODS FOR SILVER DIGIPLATE
1.1
Imagesetter
1.1.1
Output mode:
Images are output on Silver Digiplate in
negative/right reading mode, i.e. the
printing areas are unexposed (silver) and
the nonprinting areas are exposed (black).
1.1.2
Resolution:
The resolution of the imagesetter is
depending on its specifications and the
requested result.
It is important to set a sufficient imagesetter
resolution for the selected screen ruling, in order
to be able to reproduce the required grey levels.
Maximum screen ruling: 70 lines/cm (175 l/inch), 3-97%
The material is available in rolls or sheets for all standard imagesetter specifications.
6
Designation
Purpose
Packaging unit
Notes
SLM-AC Activator
Processing chemical
10l canister
Formulation:
AC+water = 1 + 1
SLM-ST Stabilizer
Processing chemical
10l canister
Formulation:
ST+water = 1 + 3
SLM-EAC Eco-Activator
Processing chemical
10l canister
Ready for use,
for Eco Processor
SLM-EST Eco-Stabilizer
Processing chemical
10l canister
Ready for use,
for Eco Processor
SDP-EACII Eco-Activator
Processing Chemical
10l canister
Ready for use,
for Eco Processor
SDP-ESTII Eco-Stabilizer
Processing Chemcial
10l canister
Ready for use,
for Eco Processor
SLM-OE III Pen
Correction pen
3-Pack
Narrow tip
SLM-OE
Correction fluid
100 ml bottle x 2
Extensive correction
SLM-OHIII
Pre-dampening
solution
5l canister
Fast ink/water
balance
SLM-OD30
Dampening solution
additive
5l canister
Conventional and
continuous-feed
dampening systems
SDP-FS
Dampening solution
additive
10l canister
Alcohol-reduced
printing
SLM-OA1
Dampening solution
additive
1l bottle
Even emulgation of
the printing ink
SLM-OA2
Dampening solution
additive
1l bottle
Increased damping
on the plate surface
Special ruling processes such as "Extra Gray Values" from Harlequin
can produce smooth runs and sufficient grey levels even with nonoptimal combinations of screen ruling and resolution.
1.2
Calculating the optimum exposure
This important task is divided into three steps: setting the laser
intensity, calibrating the screen ruling and continually checking
the results.
1.2.1
Laser intensity:
The laser intensity setting (density) has a considerable influence on
the quality of the printing results, particularly with four-colour
printing. For an imagesetter test, the processing chemicals should
ideally only be a few days old. The aim when calculating the optimum density setting is to find the point immediately preceding
the maximum blackening of the emulsion layer. It's difficult to
provide absolute guidelines for density values because the Silver
Digiplate material works very abruptly and the range between
over- and underexposure is very small.
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OUTPUT METHODS
OUTPUT METHODS
We recommend the following
process:
Carry out a test exposure of fine
positive and negative lines, e.g.
the Mitsubishi Test Chart (Fig. 1),
This test job contains several
elements designed to help you to
check the optimum exposure, e,g.
fine vertical and horizontal line
structures, fine positive and
negative text, halftone patches,
etc. The test should be carried out
several times in succession with
various different laser settings.
The selected gradations should
not be too fine, so that a good
setting may be roughly calculated
more quickly.
Free download available at
www.mitsubishi-paper.com.
Fig. 1
The exposed plates might display the following results, which
should be evaluated with a powerful magnifier (e.g. 20x):
Underexposure
Proper exposure
Overexposure
Exposure level
Reproducibility of
image with positive
and negative thin
lines
Scumming
Thickening of
dots and lines
Image blinding
Thinning of dots
and lines
Determining the Exposure Level
In principle, positive and negative lines should be equally well
defined. For subsequent printing it is important to know that
slight overexposure (more blackening on the plate) helps to prevent background scumming and filling in. Slight underexposure
8
(silver image on the plate), on the other hand, helps to stabilize
fine lines and prevent the image either from being too pinsharp
or from disappearing.
Alternatively, uncalibrated ruling dot percentage with 3% up to
97% can be output. Thereby it must be insured that no calibration
is acti-vated, otherwise the result can be falsified. In case of the
optimum exposure the 3% and 97% dot area on the plate should
be reproduced very well.
The exposure values must be calculated individually for each exposure resolution. Often, lower resolutions require higher laser settings.
1.2.2
Calibration:
The RIPs' calibration programmes offer various different ways of
influencing the output. For this reason, it is important to first establish what the calibration is intended to achieve. In general, a calibration is intended to achieve repeatable results.
Thereto two stages can be distinguished:
1st method: Linearization of the printing plate and determination
of the printing characteristics.
After completion of linearization, the printing characteristics are
determined on a print result. The characteristic then has to be
corrected for the desired standard and stored in the RIP. With this
method the preliminary stage and the print can be examined
separately in the event of any changes in the dot gain.
2nd method: Determination of the printing characteristics on a
print proof (without linearization of the plate)
The advantage of this method is that no printing plate measuring
device is required. The disadvantage is that all the influences
relevant to the dot percentages (CtP unit, printing plate, printing
conditions and printing materials) are combined in a correction
curve
To adapt the printing result of Silver Digiplate to available results
(follow-up jobs), the following method is recommended:
Produce a printing plate with a suitable test-chart with gradated
halftone patches (e.g. Mitsubishi test chart), once conventionally
with film and once by CtP. Both will be printed under the same
conditions and compared one another. Afterwards the CtP result
can be adapted by calibration to the conventional production
printing result.
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OUTPUT METHODS
OUTPUT METHODS
This will ensure that the printing results from the different
production methods can be mixed together. As alternatives to this
so-called in-house standard, calibration can also be performed to
other values, e.g. FOGRA.
1.2.3
Possible printing characteristics and how they change (all values in percent):
Computer settings
Uncalibrated proof
FOGRA values for black
on art paper
Proof with new RIP data
Caution: The numerical sequence can not be used to determine a
correct exposure, due to the fact that calibration, screen resolution and angle influences the exposure.
The aim of calibration should be to archive the in-house
standard or the FOGRA values.
Depending on the tevel of a accurary required, calibration can be performed for different screen rulings, presses,
paper sorts, etc. The right balance between cost and utility has to be found.
Fig. 3
The individual steps of calibration:
• First set the optimal density of the printing plate.
• Print out the Test Chart, method 1 (with linearization of the
plate), method 2 (without linearization of the plate)
• Proof-print under standard printing conditions.
• Measure the printing result.
• Alter the ruling percentages in RIP so as to achieve
the desired result.
Platecheck.eps
(Free download available at www.mitsubishi-paper.com)
The exposure results may vary as a result of:
• variations in or ageing of the light source.
• dirt in the optical systems.
• the processing conditions.
• insufficient processing chemicals.
• different emulsion batches of the plate material.
1.3
This calibration may be
performed either for one colour
only, e.g. cyan, or for all four process colours. The uncalibrated Silver Digiplate generally requires
heavier correction in the lightest
areas (up to 10%) and the shaded
areas (90% or more). In the midtone area, on the other hand, it is
common for little or no alteration
to be required.
Ongoing checking:
To enable a simple check to be made during production of the
optimal thickness value, Mitsubishi Paper offers digital test strips
Platecheck.eps (Fig. 3), which can be exposed at the gripper margin
of each plate. Fine lines and screen percentage facilitate an excellent
exposure judgement. This contains furthermore a specially
arranged series of digits from 10-80 which enables any change in
the density to be read off simply.
Processing
High-quality printwork and uniform results are only possible if the
processing conditions are absolutely consistent. Scratch-free, uniform processing is essential. You can check whether or not your
film processor processes uniformly with the aid of an unexposed
silver plate.
Activator
Stabilizer
Processing time:dipping-squeezing
20-30 sec.
Temperature
28-31°C
PH-value
> 12.8
Area Replenishment
150 cc/m
200 cc/m2
Anti oxidation replenishment
120 cc/h
120 cc/h
Chemicals require changing
After 2-4 weeks
Room temperature
<7.0
2
Set drying temperature at 40-50 C.
If there is a water-tray present, fill it with water.
A mains water connection is not required.
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OUTPUT METHODS
PROOFING-SOLUTIONS AND COLOR MANAGEMENT
2.0
1.4
Punching, cutting, bending
1.4.1
Punching
The current polyester imagesetters are cutting and punching the
printing plates fit for the printing machine.
Some imagesetters possess a very accurate material guide, in order
that the printing plates can be output without internal punching.
In this case the specific punching profile will be manufactured in
an aluminium plate punch.
To check and to ensure a good printing result there are many and in part
low cost proof solutions. For this purpose advantageous Inkjet-printers
are offered as well.
2.1
Application of the proofs
a. Process accompanying layout proof or color proof
It gives a survey over color and completeness of the documents.
The utilisation of color management offers advantages, but is not
indispensable.
b. Contract proof or simulation proof
The use of color management allows to originate correction prints
as coupon according to the international Norm ISO 12647-7.
c. Press or screen proof
In this place the utilisation of color management is also
recommendable. Additionally the screened proof simulates
the resolution of the printing process and its influence on the
printing result. In this way it's allowed to make defects viewable,
e.g. Moirés.
Imagesetters with integrated triple-hole film punches (e.g. Bacher
2000) require a re-punching device for the execution of the printing-plate punching. The re-punching can be performed with a
conventional hole-punch or with a special register-punch (e.g.
from Beil Registersysteme GmbH).
1.4.2
PROOFING-SOLUTIONS AND COLOR MANAGEMENT FOR
SILVER DIGIPLATE
Bending polyester plates:
Several modern types of presses, equipped with an automatic plate-loading system, require the plates to be bended. Polyester plates that are used in autoplate presses must be bended by thermal
means. The Beil and Bacher bending units are recommended for
the 4- or 8-page format.
2.2
Workflow profiling
To originate binding proofs for the four-color printing process
through color management an ICC-profiling of all involved devices
is necessary:
Fig. 4)
Thermal Bending System
Bacher 8752
Fig. 5)
Beil Thermal
Bender TPB-T
2.2.1
Fig. 4
Printing machine profiling
The profiling of the printing machine occurs through the printing of
an IT8-Chart in the own standard
(Illus.1). Consequently occurs the
measurement of the Test-Chart by
way of a color-spectrometer and
the calculation of the ICC-Profile by
way of software.
Alternatively the standardized ICCProfiles for printing from FOGRA,
IFRA etc. can be used.
Fig. 5
Illus. 1
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2.2.2
Illus. 2
Proof printer profiling
Starting from the linearization of the proof device through the printing of taper gauges (Illus. 2) and densitometric examination, a tonal
value wedges adjustment will be executed in the SDP-RIP (Illus. 3).
The ICC-Profiling of the proof device happens through the printing of
the IT8-Chart of the proof printer and the measurement by using the
color-spectrometer (Illus. 4)
Illus 3
2.2.3
2.3
Illus 4
Profiling principles
If the ICC-Profiles describes the color gamut of the printing process
and the color gamut of the proof device in an accurate mode, the
digital-proof will be much more accurate.
Usage of the ICC-Profiles on Mitsubishi SDP-RIP
The usage of the profiles in the Harlequin-based RIP-Software will
be controlled by the ColorPro Module. Input-, Emulation- and Output profiles can be defined (Illus. 5).
For generation of a digital proof, based on individual profiles, it's
recommended to use as input-profile the standard-profile from
FOGRA for offset printing or the ICC-profile,
selected and integrated by the manufacturer
(CMYK or RGB). As emulation profile the individual profile of the printing machine is selected.
In the same way ICC-profiles can be processed for
grey-scale- and spot color printing.
2.3.1
Different color gamut calculation through Rendering Intents
The SDP-RIP offers the
possibility for illustration
of different Rendering
Intents, activated and
configured by the Color
Rendering Intent
Manager (Illus.6).
Hereby it's allowed to
react on technical development trends of imparIllus. 6
tial media productions.
Picture data are stored in an increasing degree as RGB- or LabData in Media-databases (Content Management Systems) and
afterwards provided with output-ICC-profiles for the respective
operation (Print, CD-ROM, Online etc.). These profiled data can be
processed by the RIP-Software for their purpose. Every involved
device can only reproduce a determined part of all visible colors.
These different color-spaces can be transformed by way of four
different conversion methods:
a. Perceptual
This method is particularly suitable for conversion of RGB- in
CMYK-picture-data. The whole color range of the pattern will be
transformed to the color range of the output-device. It's not common with graphics or screenshots.
b. Relative colorimetric
Every hue within the capability of both devices presentable range
will be exactly rearranged. Hues outside of this range will be
converted to the nearest hue available. It's suitable for conversion
of a CMYK in the CMYK of another device.
c. Absolute colorimetric
Corresponding in large parts to the relative colorimetric conversion, additionally the exhibition of a determined paper coloration
will be computed on the output-device.
d. Saturation
This method will be used when bright colors should be
reproduced. Employment fields are presentations and businessgraphics, not often for printing.
Illus. 5
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2.3.2
Illus. 7
Mitsubishi Proof-Colourdot – the simple way to the perfect proof:
This software proofing solution offers everything for the professional proof in accordance with the FOGRA media standard, the
perfect stand proof and a brilliant photo proof. Proof-Colourdot is
based on a client/server concept, and so the
software can manage and control up to
15 printer queues of any Mac OSX or
Windows 2000/XP computer. It uses a colour
management system based on ICC profiles.
The basis for the ICC profiles is the coordinated
linearization of the printer.
Owing to various reference profiles contained
in the scope of delivery or self-generated
printer profiles, various printing processes,
starting with the classic commercial printing
down to newspaper printing, can be simulated
with Proof-Colourdot. One important criterion here is the use of
the appropriate Mitsubishi proofing paper.
The software to create your own linearizations is contained in the
scope of delivery, suitable measuring devices can also be ordered.
This provides all the conditions for the dedicated user to create his
own profiles. Special colours of a document are output directly via
the printer profile and not a reference profile. With the aid of the
PCD Colour Editor supplied any special colours can be loaded and
automatically stored in a table. If, however, no printing process is
to be simulated but pictures reproduced as accurately as possible,
Proof-Colourdot offers the possibility of RGB photo printing. Mitsubishi proofing media are ideally matched to the recommended
proof systems. The results are perfect not only for visual proofing
but also for the FOGRA media quoin.
16
PRINTING
2.3.3
Inkjet-Proof materials from Mitsubishi HiTec Paper
Mitsubishi Paper Mills Ltd. is a big acknowledged manufacturer of
Inkjet-papers as well; the German daughter company is Mitsubishi
Hitec Paper GmbH. In the Mitsubishi Paper Technical Center Düsseldorf following Inkjet-Media are in use:
MH1484 – 140g/sqm, 1-side silk-matt coated inkjet paper for layout
proof, color proof and register control. Advantageous for stand
and layout proofs, trial prints and presentations.
G1699 respectively GF160 – 160 g/sqm, silk-matt coated inkjet
paper for the "legally binding contract proof". LAB values and
media quoin results according to FOGRA paper class 1,2 and 4.
The paper is a FOGRA certified proofing substrate.
SM2574 P respectively FM170 – 255g/sqm, silk-matt coated microporous PE inkjet paper. LAB values and media quoin results
according to FOGRA paper class 1,2 and 4. The paper is a FOGRA
certified proofing substrate.
A current overview of all by Mitsubishi HiTec Paper manufactured
Inkjet-Media is available under: www.mitsubishi-paper.com
3.0
3.1
PRINTING with Silver Digiplate
Print settings
Care is required with the print settings because the water supply
to an SDP plate is not the same as that to a metal plate.
3.1.1
Setting the press:
Use the default settings, especially for the dampening rollers and
plate inking rollers.
3.1.2
Adjusting the dampening solution:
When the press first starts up, the Silver Digiplate needs more
water than a conventional aluminium plate. During production
printing the dampening solution requirements are similar to
conventional plates.
3.1.3
Additional dosing units:
Additional dosing units are available from Varn or Technotrans to
provide presses which feature cooling or winding mechanisms
with an additional dose of Mitsubishi additives.
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Seite 18
DAMPENING SOLUTION
4.0
4.1
DAMPENING SOLUTION
DAMPENING SOLUTION
Dampening Solution Additives
It is recommended to add Mitsubishi Additives SDP-FS or SLM-OD30
to the damping water. These Mitsubishi additives work in the
fountain solution to help the polyester printing plates be hydrophilic
and can also be used for printing with metal plates.
Recommended Mixture:
Conventional damping system:
SDP-FS 3% or SLM-OD30 3-5%
Continuous-feed damping system
SDP-FS 3% or SLM-OD30 3-5% + alcohol
Mitsubishi damping solution SDP-FS is for alcohol-reduced printing
and should have a pH range between 5.0 and 5.5 which is favorable
for printing.
Mitsubishi additive SLM-OD30 can not control the pH-value and
should only be applied in combination with conventional damping
solution.
4.2
Dampening solution mixing plants
Ideally the dampening solution has a water hardness of 8° to
12° dH and a pH of 4.8 to 5.5. 10-15°C are regarded as standard
dampening solution temperatures. Here, it is important to know
that too low temperatures cause condensation on tubes and
dampening solution trays and may lead to the formation of water
drops. Too high temperatures can result in toning and scumming
problems.
Modern dampening solution additives are made up so that the
correct pH is set with the prescribed dose. Buffering prevents the
paper and ink from changing the pH.
A pH measurement is not very informative with regard to the
dampening solution quality. It merely indicates whether an additive is present or not. In order to determine the quality of the dampening solution, it is also imperative to determine the guide value.
Features SLM-OA1
SLM-OA1 helps to form a uniform emulsion, and acts mainly on
the ink. The effect is similar to that achieved with alcohol or
alcohol substitutes.
Isopropanol, also designated IPA, lowers the surface tension,
increases the viscosity of the dampening solution and therefore
promotes the formation of a film in the dampening unit. This
creates uniform dampening. IPA evaporates quickly. As a result,
the ink dries more quickly and, at the same time, the printing
units are cooled by the evaporation cold. With the philosophy "A
lot helps a lot", the printers often add considerably more IPA to
the dampening solution than would be necessary from a printing
aspect. The maximum volume of alcohol to be aimed for is
5 – 10%. The IPA concentration and the dampening solution additive should be checked once or twice a week.
Features SLM-OA 2
SLM-OA 2 improves the water acceptability of the plate surface
and binds the fountain more effectively to the non-printing areas.
In order to prevent printing difficulties, it is
recommended to renew the dampening solution
every 14 days.
Additional Mitsubishi additives
The Mitsubishi additives SLM-OA1 and SLM-OA2 can be added
when required to the Fountain Solutions SDP-FS or SLM-OD 30 at
low quantities (0.5 – 2%).
18
4.3
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Seite 20
INKS
CLEANING SOLUTION AND PRINT DUSTING POWDER
5.0
STARTING UP THE PRESS
INKS
For example, the print dusting powder S 5 from KSL is recommended. The grain size depends on the material to be printed. In the
case of coarser print dusting powders (grain size 30 or 45), the
powder consists of potato starch, whereas with finer print dusting
powders (grain size 15 or 20), it consists of cornstarch. Print
dusting powder from the S 5 WL series is not suitable for printing
with polyester plates. This powder contains calcium carbonate,
and is hydrophobically treated in a special process. Print dusting
powders from the S 5 WL series are specially suited for printing
full glossy pages. This powder prevents so-called abrasive surfaces,
which are created if a normal print dusting powder is used for
glossy pages.
In principle, all offset inks are suitable for printing from polyester
plates. High-tack inks are especially suitable, as low-tack printing
inks are susceptible to scumming. The ink's tackiness can be established by tapping it on paper or between the fingers. If an ink
adheres strongly to the paper or between the fingers, it is highly
tacky, and long threads form. If the ink does not adhere strongly,
it is described as short. This resistance on the part of the ink to
cracking is called tackiness.
less tacky ink
produces short threads
tacky ink
produces long threads
7.0
7.1
Combined dampening Systems (e.g. DAHLGREN, ALCOLOR)
For some special colours, the use of more highly pigmented printing inks has proved very helpful. Using printing inks with a higher
pigmentation, less printing ink can be used in the roller mill to
obtain the same results.
Systems with a combined ink and dampening solution supply on a
single roller are usually connected to a transition roller and ductortype roller (DAHLGREN, ALCOLOR). Dampen the plate with the
dampening system before lowering the inking rollers onto it.
Use your normal dampening solution.
6.0
CLEANING SOLUTION AND PRINT DUSTING POWDER
1)
DAHLGREN dampening systems possibly require a manual
moistening with the prepared dampening solution.
6.1
Cleaning solution
2)
The ALCOLOR and other similar continuous-feed dampening
systems have a transition roller that connects the dampening
system and the inking system together. The transition roller
should be switched off.
Use a cleaning solution containing solvents to clean polyester plates
or Mitsubishi SLM-OHIII. We recommend dampening a cloth with
water and then adding a small amount of cleaning solution.
Vegetable-oil-based detergents should not be used in the roller- or
blanket-washing unit. Such detergents can leave behind an oily
film on the blanket which wears out the pores in the polyester
plates, leading to problems with scumming or smearing.
6.2
Print dusting powder
Basically, there are print dusting powders that contain calcium carbonate and those that contain potato starch or cornstarch. Print
dusting powders that contain calcium carbonate, such as K 4 from
company KSL, are not suitable for printing with polyester plates,
as this grain is very hard, and can destroy the polyester plates
during the second run (reprinting). For printing from polyester
plates, print dusting powders containing potato starch or cornstarch are suitable.
20
STARTING UP THE PRESS
7.2
Separate dampening Systems (e.g. KOMORIMATIC)
DAHLGREN
dampening System
ALCOLOR
dampening System
Dampen the plate by lowering the dampening rollers onto it until
it is thoroughly moistened (approx. 30 -40 seconds). Immediately
when the plate begins to glance turn on the ink rollers.
KOMORIMATIC
dampening System
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Seite 22
RECOMMENDATIONS FOR NON-STANDARD PRESSES
7.3
Restarting the press
PLATE CLAMPING PROCEDURE
9.0
The restart of the Silver Digiplate is comfortable; the same
methods as described in 7.1/7.2 are recommended.
Oxidation does not occur on polyester plates.
The instructions below should be heeded, in order to prevent the
SDP plate from becoming distorted:
9.1
8.0
Plate cylinder backing
Use a calibrated backing sheet if necessary. If the press specification stipulates a 0.30 mm thick metal plate and you want to use a
0.20 mm thick SDP plate, you will need a backing sheet which has
to be mounted on the plate cylinder. Mitsubishi offers special solutions for this.
RECOMMENDATIONS FOR NON-STANDARD PRESSES
Mitsubishi Paper has specific recommendations regarding settings
for many types of press. The presses mentioned here are only
examples. Further information may be obtained from Mitsubishi
Paper or from your authorized specialist dealer (see chapter 9-12).
PLATE CLAMPING PROCEDURE
9.2
Plate clamping bars
Make sure that the clamping bars are able to fix the SDP material
in position so that it cannot move. Adjust the pressure of the
clamping bars if necessary. Mark the plate close to the clamping
bars, in order to check whether it can slip out. If the mark is still in
the same place after the printing process, the pressure applied by
the clamping bars is sufficient.
9.3
Clamping the SDP plates on presses with no
autoplate system
1)
2)
3)
Clamp the polyester plate onto the front bar. If the press has a
register system, the plate is fitted onto the register pins. If not,
align the centre of the plate with the centre line on the clamping
bar. Tighten the adjusting screws in the clamping bar, starting
in the middle and working outwards. Make sure that there are
no air bubbles underneath the plate. Avoid distortion of the
plate during clamping.
Advance the press until you are able to fit the end of the plate
into the rear clamping bar. A slight tension prevents excessive
play, while too much tension may cause the plate to become
distorted.
After you have inserted the end of the plate into the rear
clamping bar, close the latter. Tighten the plate as evenly as
possible with the clamping screws.
NOTE: This process can be used for all sheet-fed offset presses
provided the register tolerance is no more than 100 micrometres.
22
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Seite 24
MULTI-COLOUR PRINTING
9.4
MULTI-COLOUR PRINTING
Clamping the SDP plates on presses with an autoplate
system
10.2
In principle, polyester plates can be used on presses that are
equipped with a semi-automatic plate loading system. There must
be no distortion whatsoever when they are clamped in the front
bar, or the infeed function will not work correctly. At present, 0.20
mm thick polyester plates are only partially suitable for presses
with multiplate Systems (fully automatic infeed).
10.3
10.0
10.1
MULTI-COLOUR PRINTING WITH SDP PLATES, TAKING
THE HEIDELBERG PM 46/QM 46 AS AN EXAMPLE
Basic machine settings and prerequisites
•
•
•
•
•
•
•
•
24
The polyester plates must be the same size as conventional
plates (505 mm x 340 mm).
Proof-print a line-forme corresponding to the
size of the run, to ensure that the press is correctly set and
obtain a suitable register mark.
Adjust the blanket to be level with bearer height.
The blanket backing should be shortened at its rear end,
so that it is not clamped in the cylinder canal. It is advisable
to fan out the backing at the rear end.
Adjust the ink rollers for polyester plates (approx. 2.5-3 mm).
Adjust the dampening roller for polyester plates
(approx. 3.5-4 mm)
The polyester plates and plate cylinder should be dry during
plate loading.
Darker ink should always be used in unit II.
Never completely tighten zone screws on the ink fountain,
also in the areas where no ink acceptance takes place.
Start-up
When the press first starts up, polyester plates need more water
than a conventional aluminium plate. They should therefore be
sufficiently dampened in advance. The following procedures have
proved effective in practice:
Lift the dampening rollers manually for approx. 20-30 seconds.
The normal set-up procedure can then be commenced.
OR
Interrupt the automatic process and print as soon as the plate is
sufficiently dampened.
The basic prerequisites for printing from polyester plates are as
follows:
•
Clamping the plates with an autoplate system
Polyester plates on the PM 46 may be clamped in the same way as
aluminium plates. In some cases, it has proved effective to use a
guide such as an aluminium plate when loading the plate, to ensure that the polyester plate is aligned with the register pins. It is
important that the plate does not lie unevenly in the crack in the
clamping bar. This can cause inaccurate register settings.
10.4
Register with polyester plates
After the press has been optimally set for polyester material, a line or
grid forme is printed out to check the register setting. The machine is
correctly adjusted if it is in-register at both the start and end of the
print run. If the press is adjusted properly and is in a good condition,
a very accurate alignment can be achieved. As the plates are subject
to a great deal of pulling when the press is started up, the use of
too few waste paper sheets can lead to inaccurate
results. For this reason, a certain number of waste
paper sheets should be printed whenever the register
marks are corrected. It should also be borne in mind
that plates that are filling in because of smearing or
scumming will use a correspondingly higher quantity of
ink, and this may lead to register inaccuracies.
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Seite 26
FOUR-COLOUR PRINTING
11.0
11.1
FOUR-COLOUR PRINTING WITH SDP PLATES,
TAKING THE RYOBI 3304 AS AN EXAMPLE
12.0
12.1
•
•
•
•
•
•
•
•
The polyester plates must be the same size as conventional
plates (335 mm x 485 mm).
Proof-print a line-forme corresponding to the size of the run
to ensure that the press is correctly set and obtain a suitable
register mark.
Packing depth 2.5 mm (blanket 1.9 mm + backing 0.6 mm).
The blanket backing should be shortened at its rear end, so
that it is not clamped in the cylinder canal. It is advisable to
fan out the backing at the rear end.
The pressure of the plate on the blanket is adjustable.
Adjust the ink rollers for polyester plates (approx. 3 mm).
Adjust the dampening roller for polyester plates (approx. 3.5 mm).
The pre-dampening phase should be computer-controlled (adjustable).
FOUR-COLOUR PRINTING WITH SDP PLATES, TAKING THE
HEIDELBERG SM 52 AS AN EXAMPLE
Because polyester plates are more liable to stretch than metal plates,
the press's basic settings must be adjusted carefully. The basic
prerequisites for printing from polyester plates are as follows:
•
•
•
•
•
•
•
•
12.2
11.2
Optimising the register printing for Ryobi 3304
SDP gauge film (underlay sheet for the plate cylinder) from
Mitsubishi is recommended for printing from polyester plates.
This gauge film ensures that the polyester plate slides more
smoothly on the plate cylinder during register setting. This
gauge film can be purchased from Mitsubishi or Ryobi dealers.
26
Polyester plates for the SM 52 should not be bended.
The length must be 454 mm, i.e. 5 mm shorter than the
aluminium plate.
Proof-print a line-forme corresponding to the size
of the run to ensure that the press is correctly set and obtain
a suitable register mark.
Adjust the blanket to be level with the bearer height.
The blanket backing should be shortened at its rear end,
so that it is not clamped in the cylinder canal. It is advisable,
to fan out the backing at the rear end.
The connecting roller between the inking and dampening
systems should be inactivated.
Adjust the dampening roller for polyester plates (approx. 4 mm).
Lateral distribution of the inking rollers must be inactivated.
Clamping the plates with an autoplate system
Polyester plates on the SM 52 may be clamped without thermal
folding on the rear edge. The polyester plate, which is just 5 mm
shorter than a metal plate, is introduced onto the register pins in
the front clamping bar in the usual manner, so that it is in-register. It is important that the plate does not lie unevenly in the
crack in the clamping bar. This can cause inaccurate register
settings. To prevent this, the front clamping bar may be opened
and closed several times using the botton. After this, the clamping
procedure can be completed by computer control.
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Seite 28
12.3
Start-up
Therefore sufficient support forces can be
guaran-teed. Using metal plates the friction clips
can remain in the machine without unfavourable
influence on the printing result.
When the press first starts up, polyester plates need more water
than a conventional aluminium plate. They should therefore be
sufficiently dampened in advance. The following procedures have
proved effective in practice.
•
•
•
•
OR (if the speed of the pan roller is very high)
bring the press to a constant speed of 8,000 rpm by turning
the feeding device on.
Heidelberg
Manual for
SM52 friction clips
13.0
13.1
FOUR-COLOUR PRINTING WITH SDP PLATES,
TAKING THE RYOBI 524 AS AN EXAMPLE
In presses with adjustable pre- and post-dampening phases, individual settings may be made specially for use with polyester plates.
•
•
•
•
During short breaks in the printing during the set-up phase,
or when the stack is being changed, it makes sense to leave
the dampening rollers on the plate.
•
•
12.4
Register with polyester plates
After the press has been optimally set for polyester material,
a line or grid forme is printed out to check the register setting.
The machine is correctly adjusted if it is in-register at both the
start and end of the print run. If the press is adjusted properly and
is in a good condition, a very accurate alignment can be achieved.
As the plates are subject to a great deal of pulling when the press
is started up, the use of too few waste paper sheets can lead to
inaccurate results. For this reason, sufficient waste paper sheets
should be printed whenever the register marks are corrected.
It should also be borne in mind that plates that are filling in
because of smearing or scumming will use a correspondingly
higher quantity of ink, and this may lead to register inaccuracies.
12.5
Plate size 510 mm x 410 mm.
Packing depth 2.60 mm (blanket 1.9 mm + backing 0.7 mm).
Adjust the dampening roller for polyester plates
(approx. 3.5 mm).
The connecting roller between the inking and dampening
systems should be switched off.
Further recommended settings as for the SM 52.
The AAC System offered by Ryobi (automatic dampening solution
quantity control) is not suitable for polyester plates.
In Series 524 Ryobi presses, the dampening roller can be adjusted
so that it remains in contact with the plate during no-load Operation. This setting means that the polyester plate is permanently
dampened during a print break, preventing over-dampening
when the press is restarted. For this reason it's very important that
the transition roller hasn't any contact to the inking system.
The recommendations for the SM 52 can be applied for
register setting.
Optimize register printing for SM 52
At register problems Heidelberg recommends the employment of
friction clips. These friction clips can be aquired at Heidelberg or
Mitsubishi International.
The purpose of the friction clips is to increase the friction on the
back of the printing plate and the lower clamps.
28
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Seite 30
POLYESTER PRINTING PLATES
TROUBLESHOOTING
14.0
Four-colour printing with SDP plates, taking the
Ryobi 784 as an example
14.1
Basic machine settings and prerequisites:
-
Plate size 745 mm x 605mm
Packing depth 2.55 mm (blanket 1.9 mm + underlay sheet
0.65 mm)
Adjust the ink rollers for polyester plates (approx. 3 – 4 mm)
Adjust the damping rollers for polyester plates (3 mm)
The connecting roller between the inking and damping system
should be inactivated
Polyester plates should not be bended.
SDP Gauge Film should be used as underlay foil for the plate
cylinder.
16.0
TROUBLESHOOTING
16.1
Exposure problems (at plate production)
Problem
Voids in image (fine lines)
Some voids in image
Slight blackening of
non-printing areas
Appearance of silver scan lines
throughout non-printing area
16.2
Scratches
15.0
Two- or four-colour printing with SDP plates, taking the
Heidelberg SM74 as an example
15.1
-
30
Plate size 745 mm x 605 mm
Adjust the blanket to be level with the bearer height
Adjust the ink rollers for polyester plates (approx. 3 mm)
Adjust the damping rollers for polyester plates (4 mm)
The connecting roller between the inking and damping system
should be inactivated.
Polyester plates should be bended by a thermal bender
Mitsubishi recommends a special packing foil as underlay foil
Underexposure
Increase exposure
Increase exposure
Probable cause
Fluctuations in processing
time in device
Contact with foreign
bodies in the device
Remedy
Check processor, rollers
and mechanism
Check rollers and guides
for crystallisation
Faulty reproduction (other causes)
Problem
Discoloured
silver image
Uneven thickness
-
Remedy
Reduce exposure, adjust imagesetter
Identify cause of scattered light
Faulty reproduction (causes associated with the processor)
Problem
Uneven image
16.3
Probable cause
Overexposure
Cloudy exposure due
to scattered light
Underexposure
Probable cause
Plate exposed for an extended
time to an intense room
illumination
Fluctuation of laser energy,
laser radiation
Activator becoming less effective
Activator temperature too low
Remedy
To prevent light penetration,
the plates should be stored
in a blackprotective case
Clean, removing dust and
foreign bodies
Replace solution
Keep solution at 28- 31 "C
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TROUBLESHOOTING
16.4
TROUBLESHOOTING
Scumming problems at printing (Precondition: well exposed printing plate)
Problem
Scumming on
the whole
printing sheet
Scumming
(staining from
emulsified ink)
Filled-in halftones
16.5
Probable cause
Activator / Stabilizer inefficient
Insufficient ink,
or ink not tacky enough
Remedy
Renew solution/check replenishment
Use high-tacky inks
Add dampening solution
SLM-OA1 or SLM-OA2
Inking rollers shifting
Prevent shifting
Dampening solution temperature too high Reduce temperature (10-15°C)
Too much varnish or thinner
Limit to 2-3%
Filter dirty
Change filter in cooling device
Incorrect proportion of thinner in
Increase concentration and check for
dampening water
suitability/ check alcohol content
Worn inking rollers
Renew inking rollers
Molleton dirty or worn out
Replace molleton
Dampening water additive not
Change dampening water additive
adjusted to hardness of water
and adjust to water hardness
Insufficient fountain solution fed in
Increase amount of fountain solution infeed
Paper dust
Depends on paper, consider
using different paper
Printing powder
Restrict use of powder or use different
powder, especially for two print-runs
Ink susceptible to emulsification
Use another ink
Too much dampening solution
Reduce dampening solution infeed
Excessive concentration of
Reduce concentration
dampening water solution
Dirty molleton blanket
Clean or change
Blanket Rollers worn out
Wash with special cleaning
agent or change
Underexposed printing plate
Adjust exposure
Inferior rendering in the printing process
(Prerequisite: well exposed printing plate)
Problem
Faulty
reproduction
Probable cause
Overexposed printing plates
Activator/Stabiliser ineffective
Inking roller pressure too high/low
Blanket pressure too high/low
Inking roller pressure too high/low
Blanket damaged
Cleaning agent not completely
removed
Dampening solution
contaminated with chemicals
32
Remedy
Adjust exposure
Replace solution/
check replenishment amount
Check inking roller settings
Adjust blanket to be level with
bearer height
Check and adjust inking
roller pressure
Replace blanket
Wipe away cleaning residues
from rollers and blanket
Before printing, ensure cleaning agent
has completely dried on blanket
and inking rollers
Empty storage container
and clean it
16.6
Voids in printing area
Problem
Probable cause
Remedy
Voids at start
of print
Ink tackiness
Processor chemical has run out
Long interruption to printing
Voids during
printing
Tacky ink
Blanket worn out
Blanket pressure too high
Molleton blanket worn out
Use less tacky ink
Add new processor chemical
Use anti-drying agent,
or advance the press further
(waste paper sheets)
Use less tacky ink
Renew the blanket
Improve the blanket-pressure
Renew Molleton blanket, possibly
replace by a softer blanket
Depends from paper, possibly
utilize different paper or utilize
an ink binder
Adjust inking roller pressure
Repair, or increase
pressure slightly
Add new chemicals/
check replenishment rate
Equalise pressure
Equalise pressure
Equalise pressure
Remove
Use clean, soft blankets
for moistening.
Paper dust
Fog
Intermittent voids
Inking roller pressure too high
Press gear wheels
deflected
Processing chemicals have run out
Blanket pressure uneven
Inking roller pressure uneven
Dampening roller pressure uneven
Dust or foreign bodies
Dirty blanket used
for etching
16.7
Poor ink acceptance
Problem
Poor ink
Probable cause
Used stabilisator solution
acceptance
Tacky ink
Insufficient pressure between
blanket and impression cylinder
Paper dust
Exposed plates were stacked
in a damp condition
during storage
Exposed plates
exposed to bright
light during storage
Remedy
Replace chemistry/
check replenishment rate
Use less tacky ink
Increase blanket pressure
Clean blanket, consider
using a different paper
Dry thoroughly before storing
Store in dark locations,
preferably in a black case
or drawer, etc.
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TROUBLESHOOTING
16.8
TROUBLESHOOTING
Poor reproduction of screen ruling points
16.11 Register alignment differences
Problem
Probable cause
Remedy
Problem
Probable cause
Remedy
Blurred screen ruling
points (duplication,
shadow formation)
Faulty unwinding
Plate has slipped
Correct unwinding
Check clamping bars, if necessary fix spray
adhesive, adhesive tape, etc., to plate
Change ink
Increase tension of blanket
Adjust pressure
Register cannot
be aligned
Plates are not correctly exposed,
punched and re-punched
Plates are not correctly
on the plate cylinder
Check plate exposure
and punching
Check whether plates are
correctly on the register bolt,
if necessary remove air enclosures
between plate and plate cylinder
Check unwinding
Check pressure adjustment
Change paper
Use paper with a different
machine direction
Shorten backing sheet, it might not
be clamped into the cylinder canal.
Ink not tacky enough
Blanket tension too low
Excessive pressure between blanket
and impression cylinder
Paper curling at edges
Electrically charged paper
16.9
Change paper
Change paper
Emulsification of ink
Problem
Ink emulsifies on
inking roller
Probable cause
pH value too high
Fountain solution infeed excessive
Ink not tacky enough
dampening solution additive
Rollers worn out
Remedy
Check pH value, consider replacing
dampening solution
Reduce Fountain solution infeed
Change ink
Faulty unwinding
Excessive pressure
Paper not flat enough
Printing material has
wrong machine direction
Blanket backing sheet
is becoming trapped at
rear in channel
Pressure between blanket
and plate cylinder too high
Plate clamping bars cannot
secure plate
Contact strips from inking
or dampening rollers to
plate too thick
Adjust pressure
Check plate clamping bars,
adjust or replace
Adjust contact strips from inking
or dampening rollers
Treat with restorative
agent or replace
16.10 Roller-stripping
Problem
Ink not distributing,
no ink acceptance
Probable cause
Fountain solution infeed excessive
Water too hard
Build-up of deposits on paper rule
Rollers worn out
dampening solution additive
Remedy
Reduce Fountain solution infeed
Soften water
Clean rollers thoroughly
Replace rollers
Subject to technical modifications.
All trademarks and registered trademarks are the property
of their owners
34
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15:28 Uhr
Seite 36
Computer-to-Plate
INTRODUCTION TO SILVER DIGIPLATE
This manual describes the characteristics of the
Mitsubishi Silver Digiplate and provides potential
users with recommendations for integrating this
method into their existing plant.
Mitsubishi International GmbH
Graphic Art Materials Division
Kennedydamm 19
D-40476 Düsseldorf, Germany
Tel.: + 49-211-4397-369
Fax: + 49-211-4397-461
http://www.mitsubishicorp-de.com
Mitsubishi Paper GmbH
Am Albertussee 1
D-40549 Düsseldorf, Germany
Tel.: + 49-211-53596-200
Fax: + 49-211-53596-222
http://www.mitsubishi-paper.com

introduction to silver digiplate technology

Transcription

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