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Controlling
Static Electricity
Winter weather provides problems
for pad printers, especially in those
areas of the country where the low
humidity associated with winter produces
static electricity. Static problems
are most prevalent when humidity is
low, because the moisture on the surface
of many materials we print makes a
good electrical conductor. When humidity
rises, so does electrical conductivity,
thus reducing static.
There are many things that you can
do to help eliminate static problems.
The plant wide approach to controlling
static means installing humidity and
temperature control systems. This
will not only control the static problem,
but will serve to minimize the effects
of seasonal changes on the entire
process by also controlling temperature.
Press setup can be reduced, because
the evaporation of the solvents from
the inks will be much more uniform
and predictable.
Short of an expensive climate control
system, a standard household type
cool air humidifier can help. If your
printer is in the middle of a big,
dry room, you may need to make a simple
enclosure with plastic to make the
humidifier more effective. I recommend
getting a little hygrometer/thermometer
and keeping it near the printer to
keep track of conditions. You can
find these at a hardware store. Ideally,
you want to be between 68 and 72 degrees
Fahrenheit with 45-55% humidity. Static
starts to be a real problem below
20% humidity.
Remember, moisture on the surface
of the substrate makes static worse.
Make sure that you allow the substrate
time to acclimate to the temperature
and humidity of the press room before
beginning production.
Slowing down the printer can also
help reduce static problems. Printing
at high speeds can generate a static
charge on the cliché, which
can transfer to the pad, which can
then transfer to the substrate. By
running more slowly, the electrical
charges around all the machine's moving
parts are held more stable.
There are two static reducing additives
for inks distributed by Service Tectonics:
1. 100-VR-1241 Special Anti-Static
Solvent can be added at 1-5% by weight.
It is available in liters for $38.00.
2. 180-PE-0013 Anti-Static Gel/Thixotropic
Raster Paste can be added at 10-20%
by weight. It is available in kilos
for $47.00.
Contact Service Tectonics at 517-263-0758
to order.
Other methods of controlling static
include grounding, using anti-static
coatings or cleaners, and ionization.
Grounding the charged material (substrate)
is difficult because bringing all
areas of the charged material close
enough to contact the grounding object
( a metallic nesting fixture) is not
always an option. Grounding the machine
is only effective if the material
being printed is conductive.
Anti-static coating and cleaners can
be applied to the substrate prior
to printing. These are usually chlorinated
hydrocarbon solutions that cling to
the substrate, reducing its surface
resistance, thus reducing static.
These can be expensive, and can require
repeated applications to the substrate
for each printing operation.
Ionization involves removing electrons
from oxygen molecules called ions.
These ions attach themselves to the
substrate to neutralize static. Ionized
air can be created by using air knives,
which create a shower of ionized air
under which the substrate passes prior
to printing. Air knives require a
power source. They can be obtained
from a static control equipment manufacturer.
Ionizing air nozzles can be attached
to a compressed air line for the purpose
of blowing the substrate off prior
to printing. Some of these also require
a power source. Nuclear neutralizers
use radio isotope emissions to ionize
the air without a power source. These
are not harmful to the operator, and
are effective provided you can get
close enough to the substrate for
them to work (anywhere from 1 to 1.5
inches). These can also be obtained
from a static control equipment manufacture.
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Monthly Newsletter
COLD WEATHER ADVISORY!
Are you pad printing with a two-component
ink system, then immediately shipping
the printed parts to your customer?
If you are, and you or your customer
are in an area of the country where
the temperature is near or below freezing
this winter, be advised.
Two-component inks may be dry to the
touch within seconds of printing,
however, they may not be fully cured
for up to 72 hours. When certain types
of two-component inks are subjected
to extremely cold temperatures prior
to the completion of their manufacturer's
recommended cure schedule, the chemical
reaction that cures the ink may stop.
In most cases, once it stops, nothing
can restart it. This means that if
you are printing and shipping immediately,
and your parts are subjected to the
cold while they are sitting in a truck
or warehouse, the ink film may not
ever achieve the desired adhesion
and/or mechanical and chemical resistance.
To be safe, we recommend that you
submit some sample parts to cold temperatures
similar to those involved with storing
or shipping, then test them for adhesion
and resistance. You can either do
this by shipping the samples to your
customer to have them tested, or by
simply putting a few in the refrigerator
or freezer overnight and testing them
yourself.
If you can't avoid having to ship
parts prior to the completion of the
inks recommended curing schedule,
the use of a hot air drying system
may sufficiently accelerate the chemical
reaction. Here again, we recommend
that you cold-test the hot air dried
parts to ensure ink performance.
In conclusion, if your customer is
seeing performance problems, it may
not be you or the ink. It may be the
weather.
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Pad Printing
Custom Colors
There are many variables involved
with correctly reproducing custom
colors with pad printing inks. For
a color match to be correct, it is
necessary for the person color matching
to have access to information regarding
the following variables:
1. The exact color you wish to match,
whether it is a P.M.S. (Pantone Matching
System) color, or a proprietary color
master.
2. The color(s) and surface characteristics
of the substrate you will be printing
on.
3. The number of times you intend
to print the color on the substrate.
4. The type or series of ink you intend
to use, whether or not you intend
to use a hardener, and if so, at what
ratio.
5. Whether you want the dried ink
film to have a gloss or matte finish.
Let's review why all of these variables
are important for proper color matching.
THE COLOR MASTER
The color(s) you wish to match will
either be a color chosen from a color
matching system or a proprietary color
that is already printed on a part
or color chip. The most popular color
matching system in the United States
is the P.M.S. or Pantone Color Matching
System. While this system offers a
lot of colors to choose from it does
have a number of important limitations.
One problem with the P.M.S. color
matching system is that all of the
colors are printed on white paper.
This is an important consideration,
since chances are you won't be pad
printing on white paper. P.M.S. colors
are also classified as being either
a "C" for being on coated, or "U"
for being on uncoated paper, resulting
in it being either a glossy (coated)
or matte (uncoated) finish. Both the
color and gloss (or texture) of the
substrate have an effect on the appearance
of the dried ink film once it is on
your specific substrate. Therefore,
the exact reproduction of some P.M.S.
colors on your substrate is not guaranteed.
It may be necessary to first print
white on some dark substrates prior
to printing bright or florescent colors.
The same holds true for proprietary
colors. The color master for proprietary
colors may be represented by a spray
painted color chip, or some other
type of color master that was produced
using pigments, applications processes
or substrates other than the one you
will use in production. All of these
variables can have an effect on the
appearance of the dried ink film.
As a rule, the more closely the materials
and process used to generate the color
master parallel those used in the
pad printing process, the better the
chances of obtaining an acceptable
match.
SUBSTRATE COLOR AND SURFACE CHARACTERISTICS
The color of the substrate is important
because, as I've already mentioned,
it will have an effect on the appearance
of the color once it is printed and
dried. Pad printing deposits a very
thin layer of ink (about 20% of the
etch depth). When we look at a color
we are "seeing" the light that reflects
back off of the ink film and substrate.
Since the ink layer is thin some light
makes it all the way to the substrate
and back through the ink to our eye,
resulting in our eyes picking up some
of the substrate's color. Furthermore,
the texture of the substrate has an
effect in that different amounts of
light are refracted or directed in
directions other than back to our
eyes. For this reason, it is necessary
to take the color and texture of the
substrate as compared to the color
master into account when color matching.
NUMBER OF PRINTS
The number of times you intend to
print is important because it determines
how much ink you'll be putting on
the substrate, and thus how much the
substrate's color will effect the
perceived color of the dried ink film.
INK TYPE AND GLOSS REQUIREMENTS
Finally, the type or series of ink
you intend to use and whether you
want the dried ink film to have a
gloss or matte (flat) finish is also
important. Ink formulations use different
resins and pigments that can effect
the finished appearance, as can the
addition of catalysts (hardeners)
and/or matte agents. For example,
the addition of a catalyst that is
clear can "dilute" the color, and
it can also increase the gloss level.
Since some inks require catalysts
and some don't, it is helpful to know
which type you intend to use so that
the color technician can add the required
amount of catalyst to the formulation
during color matching.
The only other major variable is the
amount of thinner that you will eventually
add in production. The more thinner
you use, the more the ink is "diluted",
and the more transparent it can appear
on the finished part. In most cases,
however, the amount of thinner will
not have a major effect on the finished
color.
Keeping these variables in mind can
eliminate a lot of surprises in correctly
reproducing colors with the pad printing
process.
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Pad Printing
Textured Surfaces
Textures vary according to their
individual depth, the degree of draft
on the side-walls, and in the frequency
of peaks and valleys for a given surface
area. Some textures are more difficult
to successfully print than others,
and there are certain textures that
are simply impossible to completely
cover.
In an attempt to find a correlation
between these variables and "print-ability",
I printed a series of sixty-odd black,
"visual texture standard" plaques
(provided by Mold-Tech). The plaques
were molded out of ABS (Acrylonitile-Butadiene-Styrene).
I used an automotive approved, two-component,
white ink thinned 15% by weight, a
steel cliché with an etch depth
of .001", and a 60 durometer (Shore
scale A) transfer pad. Each plaque
was single printed at one end and
double printed on the other, then
allowed to dry per the ink manufacturer's
recommendations.
Each single and double printed image
was visually inspected for coverage
under a uniform, non-directional (unfocused)
light source at a distance of 18"
for approximately 10 seconds (per
Ford Motor Company visual inspection
procedure for automotive interior
parts.) Acceptance or non-acceptance
was determined by the presence of
any visible defect or void resulting
from insufficient coverage of the
texture.
What I found was that the frequency
of the texture played a significantly
larger role in achieving an acceptable
print than the depth of the texture,
or the angle of the side-walls. One
texture having a depth of .0055" and
8 degrees draft was successfully single
and double printed, whereas another
texture that was only .0015" with
2.5 degrees draft couldn't be successfully
printed at all. The difference was
that the number of peaks and valleys
in the texture within the image area.
The obvious conclusion: the higher
the frequency, the lower the likelihood
of acceptance.
The data from my experiment only covers
a limited number of known textures
in a sea of millions. Unless you're
considering printing a part that came
from a mold textured by Mold-Tech,
it doesn't help much. So how can you
determine if your texture is printable?
Print it yourself.
In experimenting, it is important
to use a machine, cliché, ink
formulation, transfer pad and cycle
time that accurately represents what
you plan to do in production. For
example, a machine that generates
more compression than the machine
you intend to use for production may
compress the pad further into the
texture, resulting in an acceptable
print that your production machine
can't recreate. The type of cliché,
the size and depth of the image also
need to be as real as possible, as
does the ink formulation (i.e..: ink:hardener:thinner
ratio). Finally, use the same pad
shape and durometer as you'll use
in production to conduct your test.
Setup your test machine to run with
production settings for speed and
compression. When starting out, set
your compression on the cliché
and the substrate at the minimum amount
necessary to pick up and transfer
the image.
If you can't get an acceptable print
using the process you prefer, there
are several things you can change.
The easiest thing to try is a harder
pad. Contrary to what logic would
dictate, a harder pad penetrates the
texture further than a soft pad does
before the ink releases.
If a harder pad doesn't do the trick,
try slowing the speed with which the
pad compresses on the substrate. This
can make the displacement of the air
in the valleys of the texture more
efficient, leaving less potential-pinhole-causing
air under the ink film. Allowing the
pad to dwell on the surface of the
substrate for a few seconds may achieve
the same result. Some machines, such
as those having a programmable stepper
motor, can be programmed to do this.
Other machines require that the pad
be over-compressed on the part, resulting
in the machine actually stalling out.
This can result in image distortion
or worse yet, undue wear and tear
on the machine, the pad, and the part
being printed. In the event that the
pad you're trying doesn't work regardless
of what durometer you use, or how
you compress it, perhaps you need
to experiment with one having a different
angle. In this case, I have found
that the steeper the angle, the better.
On finely grained textures I have
found that if you fail to cover the
texture with a single pass, the chances
of covering it with a second pass
aren't very good. This is because
the thickness of the ink layer that
you lay down only makes the voids
(or valleys) that much deeper than
they were initially. When this occurs,
I usually revert to "bridging" the
texture, rather than continue trying
ot fill it in.
Bridging textures can be achieved
by changing how the ink film releases
from the pad. If you are lucky, this
can be achieved by simply using less
thinner, or by slowing down the machine
so as to allow more solvents to evaporate
from the ink film while it is on the
pad. This increases the tackiness
of the ink, making it leave the pad
in favor of the substrate sooner.
When the ink releases sooner, it adheres
more to the peaks and less down the
side-walls and into the valleys of
the texture. In the event that you
can't sacrifice the speed, you can
try directing some low velocity airflow
to the surface of the pad in between
image pick up and transfer. The increased
airflow accelerates evaporation of
the solvents. If you're double printing,
you may also wish to direct some air
at the surface of the part to dry
the first hit a little before the
second pass.
Bridging textures can result in the
dried ink film having less mechanical
resistance, especially when the texture
is a deep one. Since the ink is really
only adhering to the peaks of the
texture, there are tiny voids under
the ink film in between Ink that becomes
brittle can fracture at these points
more easily. Therefore, it is important
to keep the end use of the part you
are printing in mind when you are
deciding to bridge or not to bridge.
Finally, some textures are just plain
impossible to completely cover. In
these cases it is necessary for the
texture to be modified to make it
printable. This typically isn't up
to the people that have to do the
printing; it is up to the people manufacturing
the parts. If you've conducted some
of the simple experiments outlined
in this article you'll be better able
to communicate the reasons why the
texture in question isn't printable,
and your findings will undoubtedly
be an asset in determining what the
texture should be.
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Pre-Treating Plastics
for Pad Printing
Certain types of plastics require pretreatment
in order to obtain optimal ink adhesion.
Plastics from the polyolifin family
are among those that require the most
extensive treatment; with the most popular
members of the family being polyethylene
and polypropylene.
The molecules of polyolifins are linear,
and thus have no concentration of positive
or negative charges at their ends. The
coatings, inks, dyes and adhesives that
need to be applied to the plastic are
polar, adhering through the attraction
of unlike charges. Since polyolifins
are non-polar, the inks molecules cannot
adhere.
Translation: You know the last time
you waxed your car? When you sprayed
water on the hood for washing it "wet
out", or sheeted over the surface. This
would indicate that the surface had
a high surface energy (or was polarized).
Once the hood was waxed the water beads
up. This would indicate that the waxed
surface had a low surface energy. Polyolifins
are to pad printing ink what a waxed
car hood is to water. To change that
condition, we pre-treat using one of
three methods: liquid primers, flame
treating, and corona treating.
Liquid primers are blends of aggressive
solvents such as toluene and xylene
that slightly "bite" the surface of
the plastic while cleaning it. The most
popular method for applying a liquid
primer is to wipe it on with a clean
rag. (Preferably one that does not leave
a bunch of fibers behind.) If the parts
are dirty or have contaminants such
as mold release it is necessary to use
a different part of the rag for successive
parts and to discard the rags regularly
to avoid simply transferring contaminants
from one part to another. The effects
of liquid primers do not last long...
two to maybe four hours max. After treating
you should avoid touching the print
area. Make sure you have sufficient
ventilation and wear proper protective
clothing (chemical resistant gloves,
goggles, and in the absence of good
ventilation, an organic vapor respirator
may be necessary).
Flame treating is probably the most
popular form of pretreatment. A carefully
controlled flame burns contaminants
off the substrates surface while significantly
increasing the materials ink receptiveness.
Proper burner design and treatment times
are essential in ensuring that the surface
is consistently treated. Too concentrated
a flame pattern, or too much time, and
the substrate can be irreversibly damaged.
The effects of flame treatment can last
from several hours to months, depending
on the specific type of plastic. Once
again it is important not to touch the
print area after it has been pretreated.
Corona treatment (also referred to as
plasma, gas plasma or suppressed spark)
could be compared to hitting the substrates
surface with a controlled lightning
bolt. The treatment of the surface results
from bombardment and penetration of
ionized particles into the molecules
on that surface, polarizing the molecules
and increasing ink receptiveness.
The actual bombardment of the substrates
surface can be achieved several ways.
Thin flat sheets, films or parts can
be place between an electrode and a
ground, so that when the charge travels
across the gap it treats one or both
sides. This is commonly what people
mean when they use the generic term
"corona treatment". Parts having irregular
surfaces such as balls, cylinders and
blow molded containers are treated by
means of plasma (a.k.a. gas plasma),
where the charge is actually blow onto
the part with forced air. Finally, running
them through a suppressed spark environment,
which is essentially a corona filled
tunnel, can treat parts that require
"all over treatment". The method used
to apply corona discharge is thus dictated
by the nuances of each particular application.
The effects of corona treatment can
last months, however the majority of
treatment degradation takes place within
48 to 72 hours, so printing should be
accomplished within that time frame
whenever possible. In most cases the
treatment equipment is attached to the
printer or part feeding system, so this
is rarely an issue. Remember, do not
touch the print area between the time
it is treated and printed.
How can you tell if a part requires
pretreatment, or if the treatment was
successful? A water - wet test can be
easily be conducted in the field. Untreated
polyolifins have no affinity for water
(just like the waxed car hood). Once
the material to be tested is free of
dust, dirt or other surface contaminants
it should be immersed or flushed with
water (preferably distilled) for at
least three seconds. The part should
then be removed from the water and placed
in a vertical position. The length of
time the water remains on the test area
is indicative of the degree of surface
tension. If it all runs off quickly,
it requires treatment. If the water
forms a consistent film over the entire
test area and remains there for 5 to
10 seconds it is probably going to accept
ink. A very high level of treatment
can result in the film of water remaining
intact until it completely evaporates.
Another test that can easily be conducted
is to use Dyne level test pens. These
pens contain a mixture of liquids and
dyes that have specific surface tensions.
You simply swipe the pen across the
surface and observe whether it wets
out or beads up. For pad printing the
minimum surface tension should not be
below 38 Dynes / cm sq. (42 is preferred.)
These pens are available from corona
treatment equipment manufacturers and
laboratory supply companies.
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Quality Artwork
for Cliché Making
What is quality artwork? Quality artwork
is the cornerstone of any printing process.
Usually, it means a solid black image
on a clean, white or clear background.
The graphic arts industries refer to
such artwork as being "camera-ready".
The term "camera-ready" comes from the
pre-computerized days when all artwork
had to be photographed with a process
camera in order to generate a film positive.
If you are sending artwork to Service
Tectonics, Inc. for use in making clichés,
it must be camera-ready. If possible,
print your artwork out on a laser printer
two to four times size, and with the
highest possible resolution. Having
the image two to four times size and
at the highest possible resolution ensures
that the image quality will be at its
best once it is shot down to actual
size on camera, since any defects in
edge quality will be minimized. A bubble
jet printer may work if you use the
best possible resolution, but a laser
printer is better.
Examples of artwork that are not camera-ready
include: photocopies, facsimiles, business
cards, or CAD plots. Photocopies and
facsimiles do not provide an image that
is solid enough to be photographed without
voids. Business cards are generally
printed on paper that is textured, and
logos are usually too small. CAD plots
usually don't have the images filled
in solid, and the line weights are generally
too small. In applications where this
is all we get it is necessary to scan
the image into the computer and redraw
it, which takes time, and thus costs
you money at a rate of $50.00 per hour.
Electronically transferring art files
via the Internet can be a hit or miss
business. It is not always possible
to download files without discrepancies
due to the possible incompatibilities
of our system and the one you are using.
We use Corel Draw 8.0. Using this program
we can open or import many types of
files. To ensure that your file can
be opened correctly it is a good practice
to contact Bob Thompson in the art department
to ask him which formats he can use.
It is also a good idea to then send
a copy of your artwork via facsimile
to Bob for comparison, as it is not
unusual for little details to get lost
or misinterpreted by different programs,
regardless of what format they are transferred
in on.
In addition to quality artwork, proper
cliché making requires a layout.
Whether you are mailing or electronically
transferring your artwork to us, it
is useful to have a layout showing the
location and orientation you desire.
In the event that we do not receive
a layout with the artwork, we will generate
one and fax it to you for approval prior
to etching your cliché, just
to make sure we are putting the image
exactly where you want it.
Following these artwork guidelines serves
to aid everyone involved in meeting
the requirements of you and your customers.
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Warm Weather Printing
Problems
With summer's higher temperatures and
humidity come ink related printing problems.
Higher ambient temperatures cause inks
to dry more quickly, and high humidity
can cause surface tension problems.
Since the entire pad printing process
revolves around being able to control
these ink characteristics, knowing how
to compensate for changes in temperature
and humidity becomes necessary.
There are a number of ways to compensate
for higher temperatures. For those who
prefer to stick with one thinner year
round, it is necessary to increase the
amount of thinner, or decrease the amount
of time between image pickup and transfer
by speeding up the machine.
There is a fine line to negotiate here,
since too much thinner can cause the
print quality to deteriorate significantly.
The image generally becomes fuzzy or
blurred, and colors look washed out,
or less opaque. If you cannot obtain
an acceptable print with a combination
of more thinner and a faster machine
speed, it becomes necessary to go to
option two, which is "slowing" the ink
down. I'll explain how this can be accomplished
after I explain the difference between
thinners.
Most ink manufacturers offer more than
one thinner for an ink series. You usually
have a choice between a "fast", "medium"
and "slow" speed thinners. When people
refer to speed they mean evaporation
rate. For example, if you took equal
amounts of fast, medium and slow speed
thinners and poured them into puddles
having equal surface areas, the fast
thinner would evaporate first, followed
by the medium thinner, and finally the
slow thinner. You also hear the word
"retarder" frequently. A retarder is
simply a "very slow" thinner.
Slowing your ink down can be accomplished
by either using a slower evaporating
thinner in place of your current thinner,
or by mixing the two together. For example,
let's say you are using a medium speed
thinner at 15% by weight and you're
still having problems with the ink drying
on the pad before image transfer. If
your ink has a slower thinner you might
try 10 or 15% of that thinner by itself,
or if that is too slow, perhaps 10%
medium with 5% slow thinner mixed together.
This way you can slow down the ink's
drying rate without sacrificing image
quality. If you're not sure, check with
your ink manufacturer or distributor
to see if there is more than one compatible
thinner for your ink, and if they can
be mixed.
Humidity can also cause problems. When
the relative humidity is high, everything
gets water on it. Even though you can't
see it, there is water on your pad,
cliché, ink film and substrate.
Water and pad printing inks don't mix.
The ink loses its ability to flow out
into a smooth film, and its surface
tension (tackiness) becomes inconsistent
over the surface area exposed to the
air. As a result, you begin to see areas
of the image "drop out", which means
they either fail to be picked up by
the pad, fail to transfer to the substrate,
or both. To the untrained eye, this
condition looks a lot like ink that
is insufficiently thinned. While in
some cases the addition of thinner can
compensate, it is often safer to either
eliminate the water vapor by introducing
a low volume of heated airflow (a blow
dryer) to the pad, or by increasing
the ink's ability to flow by using a
flow additive, such as a thixotropic
paste.
Thixotropic paste is commonly used in
four color process printing to prevent
changes in dot sizes brought on by a
lack of flow. (In addition to increasing
the flow characteristics of the ink
it can also alleviate static problems,
which makes it equally useful during
the winter, when relative humidity is
too low.)
High humidity can also make the ink
"spiderweb". Spiderwebs are those tiny,
stingy little wisps of ink that protrude
from the edge of the print. These form
when the ink is beginning to get too
dry, when static is present, and when
humidity affects flow. Spiderwebs can
sometimes be eliminated by slowing down
the speed with which your pad lifts
off the cliché in image pick
up, and off the substrate in image transfer.
What happens when the pad lifts too
quickly is this: the outside edge of
the image is the last area to adhere
to the pad during image pick up, and
the last area to transfer during printing.
As the pad compresses, air is pushed
out the the way and the ink adheres
to the pad or substrate. When the humidity
is higher, it results in water condensing
on the ink film and pad. This condensation
acts as a "barrier" to the displacement
of the air by the pad, and it makes
the ink resistant to flow. If the pad
lifts away too quickly (before the ink
film can overcome the affects of the
increased humidity), the ink still wants
to stick to the pad, stretching as the
pad lifts away and ultimately breaking
to form spiderwebs.
If you're printing the same job all
year round, I recommend collecting some
data to make ink speed adjustments a
breeze. If you don't have a scale for
weighing ink and thinner, a thermometer,
and a hydrometer (for measuring relative
humidity), go buy them. Then, each day,
record the temperature, relative humidity,
and the amount of thinner (or blend
of thinners) you have to add to achieve
an acceptable print. After a while,
you will gather enough data to make
what I call an "Ink Mixing Matrix".
By making a chart with the relative
humidity being one axis and temperature
being the other, and then filling in
the points where the lines intersect
with the amount of thinner you had to
use, you create a visual aid for thinning
your ink. Once the Ink Mixing Matrix
is created, all the operator needs to
do is check the temperature and humidity,
refer to the chart for the correct amount
of thinner (or blend of thinners), and
add it to the ink. Presto!
Dealing with fluctuations in temperature
and humidity can be frustrating. By
experimenting with different thinners,
additives and machine speeds, and gathering
some information, you can learn to control
your process accordingly.
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For
More Information on
contracting a Pad Printer
CLICK
HERE or
Call
(517) 265-4087
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