PRINTING WITH ANCHOR ALCOHOL SUBSTITUTES

PRINTING WITH ANCHOR ALCOHOL SUBSTITUTES
PRINTING WITH
ANCHOR ALCOHOL
SUBSTITUTES
FUJI HUNT PHOTOGRAPHIC CHEMICALS, INC.
HEADQUARTERS
40 Boroline Road
Allendale, NJ 07401
Tel: 201.995.2200
Fax: 201.995.2299
www.fujihuntusa.com
MANUFACTURING FACILITY
50 Industrial Loop North
Orange Park, FL 32073
Tel: 904.264.3500
Fax: 904.278.9697
www.anchorlith.com
INTRODUCTION
CONTENTS
Our technical staff recognizes the need to provide helpful
information for pressmen and pressroom managers.
If you have any questions or comments, please feel free to call
or contact us.
Anchor Alcohol Substitutes
ARS Products
Product Features
Dosage / Directions
Anchor Two-Part Solutions
Emerald Products
Product Features
Dosage / Directions
Anchor Single-Package Solutions
Emerald Premium Products
Product Features
Dosage / Directions
What to Expect
Viscosity
Emulsification
Ink Feed
Too Dry?
Foam?
Roller Settings / Tips
Dampening Systems / Tips
Three-Roller Integrated System
Three-Roller Segregated System
Four-Roller System
Reverse Slip-Nip System
The Alcolor System
Summary
Notes
Technical Staff
Fuji Hunt Photographic Chemicals, Inc.
50 Industrial Loop North
Orange Park, Florida 32073
800.354.2300 or 904.264.3500
www.fujihuntusa.com | www.anchorlith.com
Printed in USA 3/03.
Copyright © 1993-2003. All rights reserved. No portion of
this booklet may be used or reproduced in whole or part
without our written consent.
The purpose of this technical guide is to acquaint you with the
Anchor Brand of alcohol replacement substitutes [ARS],
Emerald acid fountain solutions for use with ARS, and
Emerald  Premium single-package alcohol replacement
fountain solutions. In addition, we provide helpful techniques
for the successful use of these products.
These products are used worldwide in hundreds of pressrooms,
from the smallest sheetfed shop to many of the world's largest
web plants. You may have already read about running without
alcohol, and you may have tried some substitutes which didn't
perform to your satisfaction. The Anchor Brand of ARS,
Emerald, and Emerald Premium products are easy to use
and require only the awareness of a few differences between
their use and the use of alcohol.
We hope you find this guide to be interesting and instructive.
Please refer to our other technical guidesWater, pH, and
Conductivity For Printers and The Function of
Fountain Solution in Lithographyfor additional
information on water chemistry and the lithographic process.
2
2
3
3
4
5
5
6
7
7
8
8
9
10
11
12
13
14
14
15
16
17
18
19
20
1
ANCHOR
ALCOHOL SUBSTITUTES
ANCHOR
ALCOHOL SUBSTITUTES
Printers with continuous dampening systems are aware of the
negatives of running alcohol. The contribution to air pollution,
undesirable worker exposure, flammability, cost, and a
reduction in ultimate print quality are all drawbacks. Our ARS
products are safe alternatives to alcohol-based products.
They are alcohol-free, two-part products designed to be
used with two-part fountain solutions. When used as
directed, these products efficiently simulate the performance
of alcohol without the undesirable side effects.
Product Features
ARS Products
ARS-JP is a strong alcohol replacement, proven to be effective
on presses equipped with continuous dampening systems. It is
recommended for Dahlgren type dampening systems.
ARS-ML, proven to be effective in eliminating alcohol on a
variety of sheetfed presses, will quickly achieve optimum
emulsification for easy ink/water balance. It is recommended
for Heidelberg Alcolor dampening systems.
ARS-WL offers a wider than usual ink/water balance window
more like alcohol. It contains no HAPs solvents and is safe for
all CTP plates. It is an excellent choice for UV and hybrid inks.
ARS-X contains no HAPs and is proven to be effective in
eliminating alcohol on presses equipped with continuous
dampening systems. It is recommended for the Crestline and
Kompac dampening systems.
2
• Non-flammable.
• Reduces VOC compared to alcohol use.
• Designed to be easy to run.
• Will not alter conductivity readings.
• Offers a wide ink/water balance more like alcohol.
• Reduces ink feedback, eliminating the need for frequent
maintenance and cleaning of the dampening rollers.
• Minimizes adjustments and tends to compensate for the
effects of alcohol.
• Provides variable wettingas more is used, greater surface
tension reduction will occur.
Dosage / Directions
Use 2 to 4 ounces per gallon, as needed, to replace alcohol and
achieve the desired level of wetting power. To use, pour
directly into dilute fountain solution.
3
ANCHOR
TWO-PART SOLUTIONS
ANCHOR
TWO-PART SOLUTIONS
Emerald Products
Product Features
The Emerald brand of fountain solutions have become a
standard in the graphic arts industry. As two-part [or twostep] solutions, they are specially formulated for use with
alcohol substitutes or alcohol.
Please refer to our product data sheets for specific product features
and to find the appropriate product for your specific needs..
Our most popular Emerald product is the “JR” series. These
are designed with built-in drying stimulators which decrease the
setting and drying time of ink. They are available for a variety of
water conditions and designed to meet additional specific needs.
• The fastest start-ups.
• JRDeionized to soft water.
• Excellent non-piling performance.
• JRHHard water.
• Reduces feedback on continuous dampening systems.
• JRMMedium water; good for CTP plates.
• Elimination of problems with alkaline papers and aqueous
plates.
• JRTSoft to medium water; specially formulated to run on
aqueous plates.
Dosage / Directions
• JRZSoft to medium water; is a low phosphate product
that helps to control calcium.
Our other popular series include low VOC, PF [phosphatefree], and the original Emerald products.
4
• Wide latitude of operation.
• Clean reverses with the sharpest dot and excellent
halftone reproduction.
Emerald JR fountain solutions run best when excessive use is
avoided. The majority of these two-part products have been
designed to run at a starting concentration of 2 to 3 ounces
per gallon. If required, this dosage can be increased to provide
stronger desensitizing. It is recommended that you verify pH
and conductivity of the press-ready solution by preparing a
control sample using local water at the desired dosage. Record
the pH and conductivity to serve as your target numbers.
5
ANCHOR
SINGLE-PACKAGE SOLUTIONS
ANCHOR
SINGLE-PACKAGE SOLUTIONS
Emerald Premium Products
Product Features
These single-package or one-step products are “total”
solutions. They are formulated with both fountain solution and
an alcohol substitute, are available for both sheetfed and web
presses. Some of our popular series include:
Please refer to our product data sheets for specific product features
and to find the appropriate product for your specific needs.
• MXEH SeriesThese are the original formulas that solved the
ink feedback problem on web presses running zero alcohol and
have the widest ink/water windows of any fount on the market.
These are recommended for small presses using Crestline and
Kompac dampening systems.
• KDM SeriesThese are low VOC solutions. KDMA has
increased phosphates for fast restarts on PDI plates.
KDMC is recommended for thermo CTPs and is the TEC
compliant version of KDMA for presses with catalytic
converters.
• Q Series CPQ has a strong buffer system that is good for
alkaline papers. PAQ has phosphates for faster restarts and
a wider range of waters. PAQ-P is best for polyester plates.
PAQ-R controls blinding and stripping often associated with
running coated paper. PAQ III eliminates the blinding often
associated with aqueous plate images.
• WOGThis is a high-dose sheetfed product for use in soft
to medium-hard water. It contains extra phosphates for fast
starts and restarts and is compatible with all types of plates.
6
• Single-package product combining fountain solution and
alcohol substitute for blending ease.
• Contains the finest gum arabic.
• Contains phosphate for faster restarts.
• Excellent buffer system which retards calcium blinding and
roller stripping.
• Reduces ink feedback into the dampening system.
• Replaces alcohol at 5 ounces per gallon, in most applications.
Dosage / Directions
The majority of our one-step fountain solution have been
designed to run at 5 ounces per gallon. For optimum
performance, the suggested starting concentration for some of
these solutions may differ slightly depending on your needs. It
is recommended that you verify pH and conductivity of the
press-ready solution by preparing a control sample using local
water at the desired dosage. Record the pH and conductivity
to serve as your target numbers.
7
WHAT TO EXPECT
WHAT TO EXPECT
When running alcohol substitutes, you can expect some differences in
key properties over running alcohol products.
Emulsification
Viscosity
An important difference between running alcohol and running ARS or
Emerald Premium products is the viscosity of the solutions. A
solution of 10% alcohol in water is almost twice as viscous as the
water itself, and about 30% more viscous than fountain solutions
containing our alcohol substitutes. This affects the rate at which
the dampening system can deliver the fountain solution.
The higher the viscosity, the faster the dampening system will send
fountain solution to the plate. The lower the viscosity, the slower the
delivery rate. In other words, with alcohol substitute products, your
dampening system will deliver up to 30% less fountain solution to the
plate as it would with alcohol.
How big a problem is this? With a few exceptions, most dampening
systems only need to be run about five to ten percent fastera dial
change from 4 to 5to provide adequate volumes of our fountain
solutions to dampen the plate completely. If it is necessary to
increase the dampener speed by more than 50%, try reducing the
roller pressures in the dampening system.
Alcohol is such a strong ink emulsifier that pressmen try to run plates
as dry as possible, since experience has shown what will happen if they
do not [emulsification]. At the same time, the pressman running
alcohol substitutes is confronted with a higher dial speed and will
instinctively turn the water dials up just enough to clean the
background. This interferes with starts and restarts due to an
inadequate supply of water and prevents adequate protection of the
plate.
Alcohol substitute products are non-emulsifiers, so it is not necessary
to run plates as dry as possible. In fact, we recommend that plates be
at least as wet as when running alcohol. This will result in better
ink/water balance, instead of constantly being in danger of running
too dry.
The best way to determine whether a plate is getting the fountain
solution it needs is to look at it while the press is running. If it looks
dry, it is dry. If it looks wet and shiny, it is too wet. We recommend
that plates be run with just a light sheen of moisture. If a plate is run
too dry, it will transfer ink across the background to the blanket
faster. This will lead to piling or "picture framing" on the blanket.
If dial speeds cannot be lowered into an acceptable range, try
increasing the diameter of the metering roller a few thousandths of an
inch. This increases the surface speed of the metering roller in relation
to the roller against which it rides.
8
9
WHAT TO EXPECT
WHAT TO EXPECT
Ink Feed
For the first week or so of running without alcohol, we
recommend starting the run with low densities, bringing the
job up to color as the make-ready progresses. This way, you
will quickly become accustomed to the new ink requirements.
Another important difference between alcohol and our products
relates to emulsification and ink feed. The idea of alcohol as a
"wetting agent" is widely accepted, but is an oversimplification
of what alcohol does. When running alcohol, the fountain
solution wets not only the plate background, but the image
area of the plate and the ink. This reduces the efficiency of
transfer of ink to the plate. When running without alcohol,
only the background of the plate is aggressively dampened. The
image area of the plate and the ink remain fairly dry. This
allows a much more efficient transfer of ink from the rollers to
the plate, thus reducing the amount of ink needed in the rollers
to get the same ink density on the paper.
The press has specific controls for the replacement rate of ink
[the ink ratchet and keys], but there is no control for how
much ink is in the rollers. This is determined arbitrarily by the
pressman when the press is inked up. If the ink system is
overcharged with ink, ink/water balance can still be achieved.
However, this balance will not be as stable as one based on an
ink volume more in line with demand.
Trying to maintain a large volume of ink will create a situation
where the amount of ink in the rollers increases during the
press run, increasing the demand for water. The larger the volume
of ink in the rollers, the higher the demand for water will be.
If the press starts to demand more water as the press run progresses, gradually cut back on the ink feed rate, and the
demand for water will diminish quickly.
10
Too Dry?
Pressmen often instinctively run the plates as dry as possible.
Long before the plate got dry enough to cause any other
problems, it would scum from lack of moisture. It is possible to
run the plate too dry when using Emerald Premium or ARS
products; in fact, it is the most common source of trouble.
It is recommended that you take a frequent look at the plates
during the first few press runs to be sure that the plate doesn't
look dry, but has a light sheen of moisture on the surface. If
run too dry, you may see ink on the blanket outside the sheet
or web area, faster blanket piling, feedback into the dampening
system, contamination of the circulator, narrow ink and water
balance, or slow restarts.
If the plate isn't scumming, how can it be too dry? The
answer is that Emerald Premium and ARS products are so
effective at desensitizing they will tend to keep the background
clean with a very thin film of water. Remember that with
alcohol, the solution is more viscous and the film delivered to
the plate is thicker. The plate needs to be protected physically
by a layer of water thick enough to keep ink out of the grain of
the plate.
11
WHAT TO EXPECT
Roller SettingS / TIPs
Foam?
Because alcohol does a good job of wetting the ink, the ink
form rollers behave a little like extra dampening rollers, helping
to wet the plate. This interferes with the ink rollers doing their
job of inking the plate. When Emerald Premium or ARS
products are used, the ink in the ink system will remain dry.
This means you will dampen with the dampening system and
ink with the ink system. Many pressmen have remarked,
"When I add alcohol, this mark, or that streak, or this toning,
goes away!" However, if they were to lift the ink rollers and
briefly print with only the dampening system, the problem
would reappear.
Because alcohol is a good bulk defoamer when used in large
quantities [5% or more], many pressmen have foam problems
when it is eliminated. Foam is created from the mixture of air
and water by the circulating pump when the fountain solution
is returned from the tray to the tank, not by the pressure used
to do this. The pump will mix the air and water together very
effectively, regardless of the pressure used. If foam is a big
problem, you may be able to disconnect the return lines from
the pumps and rely on gravity to return the fountain solution
to the tanks. This will prevent the formation of foam.
Emerald  Premium and ARS products have excellent
defoaming capabilities, but have little reserve defoaming power
to overcome foaming pressures from other sources. Many
commonly used presswashes and plate cleaners contain strong
foaming ingredients. If these materials are allowed to get into
the fountain solution and the circulator aerates the solution
much, foaming will occur.
To eliminate foaming, once it occurs, you need to identify which
products are causing the foaming and either change to a nonfoaming alternative, or take precautions to prevent any of these
materials from entering the dampening system. A good way to
identify a foam source is to place some of the suspect material in
a tall container with water and shake well. If a big head of foam
forms and does not dissipate quickly, this is certainly something
you would like to keep out of your fountain solution.
12
Many systems have an adjustment that allows more water to
be fed at the ends of the system than at the middle. This is
referred to as the "skew control."
It works by swinging one of the rollers [usually the metering
roller] out of square with the chrome roller. This relieves the
pressure at the ends, allowing more water through. When the
skew control is set at zero, there is actually less water put
through at the ends than in the middle. When Emerald
Premium or ARS products are run, the solution's lower
viscosity usually requires more skew than with alcohol.
13
Dampening Systems / TIPS
Dampening Systems / TIPS
Most continuous dampening systems fall into one of three
categories: 1) three-roller integrated system, 2) three-roller
segregated system, and 3) four-roller system. Each has
advantages and disadvantages. One thing they have in common
is that without alcohol, it is probably best to run with minimum
metering pressure to ensure an adequate transfer of fountain
solution through the metering nip.
Three-Roller Segregated System
A three-roller segregated system often contains four
rollers; but, with or without bridge rollers, they share the
same characteristics.
Three-Roller Integrated System
This system runs very well without alcohol, as long as the form
roller is driven by the ink vibrator instead of the plate. Simply
put, this means having the form roller tighter to the ink
vibrator than it is to the plate. This will prevent streaking and
toning at the lead edge of the plate by ensuring that the form
roller speed is constant, rather than changing as the plate
cylinder comes in and out of contact with the plate.
14
This system relies on gear drive for their form roller speed, so
the pressure settings of the form roller are not critical. It is
important that the pressure between the form roller and the
chrome roller is not so tight as to interfere with the transfer
of water from the metering rollers to the form. The efficiency
of this system is largely dependent on the gear ratio used by
the manufacturer to drive the form roller.
15
Dampening Systems / TIPS
Dampening Systems / TIPS
Four-Roller System
Reverse Slip-Nip System
These come in two layouts with one variation. In this system
it is important that the form roller is tighter to the vibrator
than it is to the plate. This is to ensure that the form roller
speed remains constant.
This is a variation of the four-roller system. The advantage of
the reverse nip at the slip contact is that a reservoir of liquid
builds up, increasing the systems throughput.
These systems may be the easiest to run without alcohol.
If the form is gear-driven by the vibrator, then the settings
are less critical.This system has the reputation for "feeding back" or
allowing ink to accumulate on the metering or slip roller.
Emerald Premium or ARS products will prevent the plates
from running at an inadequate level of dampness. This will
ensure that there is a proper flow of water through the
dampening system to keep the flow of ink and water "one
way."
16
17
Dampening Systems / TIPS
Summary
The Alcolor System
We have presented a lot of information covering a wide range
of topics related to running without alcohol. However, the two
main points are as follows:
This four-roller system has a unique layout. It is important that
the form roller be driven by the vibrator rather than the plate,
but this poses a difficulty.
1. When running alcohol, the main concern is to avoid running
too much water and prevent emulsification. Without
alcohol, the opposite situation existsyou must be sure to
run enough water.
2. Also, you must be sure to carry less ink in the ink rollers.
If the rollers are charged with the same volume of ink
necessary to print with alcohol, it will lead to problems
with ink/water balance, trapping, drying and the build-up of
ink where it is not wanted.
As you tighten the pressure from the form to the vibrator, you
start to exclude liquid from the form roller. This system is
more dependent on the solution's viscosity to provide
adequate throughput than other systems.
Since our products have a viscosity of about 30% less than a
10% mixture of alcohol and water, the motor speed must be
increased about 30% to get the same amount of liquid through
this system. This does not mean that more water is being used.
With the Alcolor System, care must be taken to ensure that
enough water is run. The natural tendency is to turn the dial
up just enough to clean the background, but this will leave the
plate too dry. Make sure the plate has a light sheen of
moisture on it throughout the run.
18
Eliminating alcohol-based materials and replacing them with
more compatible materials can be a great source of frustration.
When inks, plates, paper, etc. were evaluated in the past, it was
assumed that they were evaluated solely on their meritsthey
either worked or they didn’t. This approach did not take into
consideration that these products were never judged on their
individual properties, but on how well they fit into the existing
alcohol-based printing system. Many materials in pressrooms
would never have been purchased if alcohol had not been in
use.
It is our hope that this booklet will assist you in running alcohol
substitutes or even help you to make the switch from alcohol
to alcohol-free solutions.
19
NOTES
20
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertising