internship report
TRANSCRIPT
DIC PAKISTAN LTD.
Internship Report.
Research Internee. (LUMS-SSE)
Muhammad Yasar Qamar 18th July to 13th August (2011)
This report, submitted to Dr. Asad Javaid (Technical Manager, DIC), contains detailed analysis of different instruments and techniques that can be employed by DIC to further improve the Quality and Assurance of manufactured inks. Subjects focused include Viscosity, Lamination Strength in Peel Tests, and Surface Tension.
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TABLE OF CONTENTS
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Viscosity of Inks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Viscosity Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Lloyds Digital Chrono Thermo Viscometer . . . . . . . . . . . . . . 12
Test Certificate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Lamination Strength Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
90 & 180 Degree Testing Techniques . . . . . . . . . . . . . . . . . . 16
Experimental Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Recommendation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Surface Tension of Inks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Basic Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Application Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Specifications of Delta-8 Analyzer . . . . . . . . . . . . . . . . . . . . . 28
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
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INTRODUCTION & OVERVIEW.
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Introduction
My internship at DIC Pakistan Limited (Dainippon Inks and Chemicals) introduced me to the
world of ink manufacturing. It has been mainly a learning experience for me throughout where I came to
know the different kinds of inks that are produced. The two main types are Liquid based and Oil based
(Offset). I was, also, made aware of the many different techniques that are being used to produce
colored inks as per the requirements of customers.
The first week of my internship was an Orientation of the Chemical Laboratory as well as the
Production Plants. I met a dedicated team of chemists working at the lab who provided me with
firsthand knowledge about their own work.
First of all Muzammil Sb. gave me a detailed background about the history of DIC and its various
branches working all over the world including Pakistan. Along with this he provided me valuable general
information about the work environment in professional jobs. Khalid Sb. taught me the fundamentals of
raw materials used in the making of inks. These are namely pigments, additives, resins and solvents.
Khurram Sb. showed me how shades of customer samples are first prepared and made. He then helped
me in making up different ink samples using recipes contained in the SAP.
Systems and Applications Product (SAP) in Data Processing is a data base containing all the
standard recipes of hundreds of ink samples. I used its CS-13 feature to search for the contents and their
masses that make up Silver ink. Then I weighed these contents using a mass balance and mixed them
using a mechanical stirrer. This ensured a uniform mixing of contents in the bottle. After this I measured
the viscosity of the ink using Zhan cup-2 for flexographic inks and ensured that it was within the
acceptable range of 18 to 19 seconds. This exercise gave me a technical insight into the processes
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through which Quality Checks are ensured so that the manufactured inks fulfill customer and industrial
requirements.
This was followed on the next day by a guided tour of the Offset production plant. Irfan Sb. gave
me a detailed overview of the processes by which inks were being manufactured on a large scale. These
were basically grinding, weighing, mixing and rolling the concentrates from a raw state to a semi-
finished one. Varnishes are also added to give a gloss to inks. Samples of these semi-finished
concentrates are then sent to the Technical Laboratory where different tests are conducted to ensure
Quality assurance. These include testing the color strength, particle size, flow, and viscosity among some
others. Once prepared the concentrates are stored in a semi-finished state for later use. The feature
that impressed me in this section was the Rolling machine which grinds ink particles to a very fine size. I
saw that manual as well as automated machines were being operated which were mainly of a three
cylinder design.
Moving on I proceeded in my internship with a detailed overview of the Laray Viscometer and
learned that it determines the viscosity value in the offset oil inks. I started a mini project with Haider
Sb. regarding viscosity of fluids. I was asked to read about the basics of viscosity including the different
units that are used to measure it and then to compare the merits of both of them. I read from different
resources about viscosity and also frequently discussed it with Haider Sb. These discussions proved to be
extremely useful for me as they helped me to improve my concepts about viscosity, and I am extremely
thankful to Haider Sb. for helping me in learning these concepts.
In the next half of my internship I was assigned two main projects by Dr. Asad Javaid. The first of
these was testing Lamination Strength using the instrument Lloyds. I was asked to learn its different
functions and, also, to check the effectiveness of the methods currently used at DIC to test lamination
strength of different samples. The second project was an independent study regarding Surface Tension.
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Starting on my first project Ms. Shabana taught me the basic working principles of Lloyds. She
gave a practical demonstration and did a sample test on the machine. She briefed me about the 90
degree peel test method. The Lloyds software gives the user a custom control over different testing
parameters, the values of which can be altered to check variations in the lamination strength value.
Lloyds, also, has a graphic output which is displayed on a computer connected to the machine. Different
samples are tested and the results are stored in the computer which has a database of all the previous
test records. These can be accessed anytime for later reference.
I tested different samples of ‘Capri Soap’ packages for their lamination strengths. Each sample
was tested twice; once before heat seal (Before HS) and the other after heat seal (After HS). This was
done so that the effect of heat on lamination strength can be noted. A number of samples of the same
package were tested so that variations in the complete package roll were accounted for.
For the project part, I tested different samples using two different techniques on each of the
samples. The results and conclusions of this study have been compiled later in this report.
Overall, the experience here at DIC proved to be good for me as I engaged in research over many physics
related concepts. . I enjoyed working on three projects simultaneously which at first seemed difficult but
was made very manageable with help and support by almost everyone involved in the technical
laboratory. This allowed me to learn many different things in my research based internship and provided
an insight into the technical challenges and problems in an industrial set up All in all, I am extremely
thankful to everybody who made my experience memorable.
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VISCOSITY OF INKS.
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Viscosity Analysis.
Definition:
To put simply, viscosity is an internal property of a fluid that offers resistance to flow. A more
formal treatment defines it as the ratio of the shearing stress to the velocity gradient.
Types:
i) - Dynamic viscosity
ii) - Kinematic viscosity
Units:
Pascal second (Pa.s) [S.I. unit for dynamic viscosity]
Poise (P) [cgs unit for dynamic viscosity]
Stokes (St) [cgs unit for kinematic viscosity]
These units are fairly large and are rarely used. In normal practice centipoise, dyne second per
square centimeter and centistokes are used.
Conversion factors:
1 pascal second = 10 poise
1 centipoise = 1 millipascal second
1 cm2/s = 1 stokes
Generally, the cgs units are preferred over the SI units for the measurement of viscosity for two
reasons. Firstly, most scientific and technical publications use cgs units for viscosity because of which
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these units are much more common than the SI units. Secondly, since cgs units are smaller they are
more appropriate for practical measurements of viscosity than SI units.
Instruments at DIC:
Two different instruments are used to measure the viscosities of inks in the lab. at DIC.
Zhan Cups for liquid inks.
Laray Viscometer for oil based inks.
Zahn Cup:
Zahn cup is a cup made of stainless steel with a hole at the bottom of its centre. To measure the
viscosity of the ink, the cup is filled with it and ink is then allowed to flow through the hole. The time
taken for the flow of ink to break is noted using a stopwatch. For different values of viscosities different
standard times are set and the measured times are compared with these to check for the viscosity of the
ink. The typical time which I used was 18 seconds.
Zhan cups also come in different sizes as per the viscosity of the ink measured. For high
viscosities large number cup sizes are used, and for low viscosities low number cup sizes are used.
Laray Viscometer:
The Laray Viscometer determines the viscosity of viscous materials by measuring the
time required for a rod to travel a specified distance. Viscosity is calculated using this time. A heating
system is also attached to the equipment which makes it possible to test the viscosity at different
temperatures. A water circulation jacket is used to provide heat to the ink which is coated on the
testing rod. In the lab at DIC, a water bath is attached to the Laray Viscometer and the temperature is
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set to room temperature i.e. 25 ‘C. Graphical output is displayed by using a computer program. Normally
weights of masses 400g, 600g and 800g are used for high viscosities.
As part of my research, I looked up for other viscometers available in the market. I found a much
better one in the Lloyds Product Catalogue.
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Lloyds Digital Chrono Thermo Viscometer.
Purpose:
To measure accurate Viscosity and Yield Value of inks, Varnishes and other viscous materials in
the development of ink formulation.
Method:
Falling Bar Principle (Larry Method).
Range:
40 – 2500 poises.
Model 92N:
Featuring advanced microprocessor based electronic with infrared control. Lloyds Viscometer
provides the highest accuracy and efficiency for research and development, quality control and process
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evaluation. A most important instrument used in the manufacturing of high quality printing inks and
varnishes to control viscosity and yield values at various stages of production, and accurate quality
control of production batches without any chances of rejection or reworking.
Advance Features:
• Confirms to ASTM D4040
• Microprocessor based electronics for high reliability and accuracy
• Simple and fast method of test and easy to operate
• Only 2 cc of test sample required
• Steel Viscobar and glass Viscobar (for low viscosity i.e. liquid ink, etc.)
• Failsafe auto manual electronic design with auto zero for minimum testing time
• Nil or Minimum maintenance needed
• Best for regular production and for developing accurate formulations and R & D work
LLOYDS Viscosoft Software:
Lloyds Viscometer is further backed by specially designed Lloyds Viscosoft
software that will directly calculate without the need of manually plotting Larry Viscosity Graph the
accurate viscosity, yield value and shortness ratio or S.R.index of an ink with test certificate for achieving
perfect formulation. A very important tool for quality control and R & D laboratory.
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Advance Features of the LLOYDS Viscosoft Software:
• Accurate, Instant and repeatable test results of viscosity, yield value and shortness ratio of an ink with
test certificate without manually plotting the Larry Graph
• Can recalculate Viscosity, yield value and shortness ratio at any other given temperature without the
need to perform the test at that temperature
• Advance inbuilt features to measure viscosity under temperature variations with correction factor
• Online comparisons of test results or with set standards
• Calibration through software require only dimension of orifice and Viscobar. No special standard
tested fluid or representative ink required to calibrate the viscometer. Simple Calibration technique in
software to maintain instrument consistency and takes care of Viscometer wear and tear.
Accessories:
• Glass Viscobar for low viscosity measurement with calibrated weights for low viscosity i.e. liquid ink,
resins etc.
• Viscosoft software for calculating viscosity, yield value and shortness ratio without plotting the graph
manually
• Refrigerated water bath for maintaining accurate test temperature of viscometer
Electrical characteristics:
• 230/110 Volts 50/60 Hz
• Less than 10 Watts power consumption
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Dimension & Weight Details:
• Unit physical dimension -12”W X 6”D X 15”H - Net Weight 23 Kgs
• Shipping Dimension - 21”W X 12”D X 19”H - Gross Weight 40 Kgs
Conclusion:
Lloyds Viscometer is one of the best instruments to test the viscosities of inks and varnishes
in laboratory. It gives the user enhanced control over many features that can be used to set parameters
under which a sample of ink is to be tested. Since these parameters can be changed easily, the Lloyds
Viscometer can also be used for research and development regarding the manufacture of better quality
inks. Moreover, the comprehensive result output gives a detailed overview of the test conducted. A
sample of a Test Certificate has been copied on the next page:
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LAMINATION STRENGTH TESTING.
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Peel Strength Testing using Lloyds LRX Plus with 90 and 180 degrees.
Lloyds LRX Plus:
It is a materials testing machine that can be used to perform various tests on inks
related products. It is capable of tensile, compression, flexural, peel, shear, friction testing and more up
to a load limit of 5 KN. The LRX in the laboratory at DIC is used to check the lamination strength of inks
and adhesives on different market products. The instrument is fully PC-integrated and results are
calculated and displayed on a computer using the NEXYGEN™ MT Materials Test and Data Analysis
Software.
Differences in Results between 90 and 180 degrees techniques:
Peel adhesion is defined as the force
required to remove pressure sensitive coated material under specified conditions from a film at a
specified angle and speed.
Peel strength testing or De-lamination strength testing is basically carried out using two
angle-based techniques, 90 and 180 degrees. I carried out a number of tests on different samples under
the supervision of Ms. Shabana using both of these techniques. The results of these experiments are
tabulated on the following page:
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DIC PAKISTAN LTD
----------------------------------------------------------------------------------------------------------------- ISSUED BY: LAB
CC: I/C Lab Dated: 05.08.2011
SUBJECT: Lamination Strength Results of Lifebuoy 155g & Knorr Garlic Sauce 10g using
90 degree and 180 degree peel-test angle techniques
Identification Key:
CIT: Complete Ink Transfer Blue: Lifebouy Sample
PIT: Partial Ink Transfer Green: Knorr Sample
FT: Film Tear
PET: Poly-Ester
MPET: Metalized Poly-Ester
Reel# Description Lamination
Structure
Lamination Strength(g/cm)
90
Degree
180
Degree
Comments
90 Degree 180 Degree
142 Blue Area PET+PAPER 93.144 164.54 50% IT FT
58 Blue Area PET+PAPER 79.645 140.10 50% IT FT
18 Green Area PET+MPET 69.776 98.402 CIT CIT
43 Green Area PET+MPET 108.30 141.46 CIT CIT
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Results:
Based on the data acquired, two major observations are:
The 90 degree peel-test gives a lower value of lamination strength than the 180 degree
test.
The 180 degree peel-test often produces a Film Tear (FT) in the sample. This can be
seen in the case of Lifebouy sample.
Conclusions:
There are various reasons that give rise to an anomaly in the values for 180 degree peel test
compared to the 90 degree peel test. One of the major reason is that using a 180 degree technique on
the Lloyds instrument requires the strip to be bent using your hand. This increases the load to be pulled
by the upper jaw, hence increasing the value for lamination strength. Moreover, there can be human
error involved in this technique too since the increase in load value varies from user to user. The 90
degree method does not require the use of hand which eliminates any possibility of human error in the
readings.
180 degree peel tests often give a film tear (FT). The Lloyds Data Acquisition Software
NEXYGEN calculates an average value of lamination strength based on the readings throughout the peel
time. When a film tear is produced the reading drops to zero and stays constant there onwards. This
leads to an incorrect value for lamination strength to be calculated because the average value also takes
into account the zero reading.
Nevertheless, in some countries 180 degree peel test technique is being used to test the
adhesive strength between inks and lamination structures. For instance, at DIC Japan both 90 and 180
degree angles are popularly used. But this is done as per the demands of the customers who require the
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samples to be specifically tested either for the 180 degree or 90 degree peel. At DIC Pakistan the
customers do not have any specific requirement for the angle to be used for peel test. Hence it is
entirely up to the technicians to test the sample with an angle that gives the most suitable results.
Recommendation:
Lamination Strength is a very important factor for Quality Assurance and Maintenance
as well as Research and Development regarding ink manufacture. The 90 degree (T-shape) peel test is
the most suitable angle test for testing lamination strength at DIC Pakistan Limited. This is because the
90 degree method gives precise measurements and allows values to be measured for materials normally
giving film tear.
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SURFACE TENSION OF INKS.
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Surface Tension: Basic Overview
The content for this section has been drawn from a technical report in the Research Section of CFFA
(Chemical Fabrics And Film Association).
Introduction:
Wetting is a phenomenon that we see every day. In simple terms, it is the ability of a liquid
to spread across the surface of a solid to produce a uniform, continuous surface. How a solid is wetted
by a liquid is measured by the surface tension of the liquid relative to the surface tension of the solid.
For a coating, adhesive or ink to be usable it must a) wet and adhere to the substrate, b) cure, and c)
exhibit excellent enduse properties. The surface tension of solid, also, has important influence on these
properties. A solid surface with intimate coverage of a liquid is necessary to produce a strong uniform
adhesive, coating or ink bond.
Units:
S.I. Unit – Newton per meter (N/m).
CGS Unit – dynes per centimeter (dyn/cm).
It is usually measured in the cgs unit of dyn/cm (dyne per centimeter).
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Theory
Surface Tension:
The interactions at the interface between a liquid and solid are complex but have
practical importance. For a drop of liquid to spread across the surface of a solid (wet the surface) work
occurs to change the shape of the liquid drop. Surface tension is the work per unit area to reshape the
liquid. It is measured in dynes/cm. For a liquid to wet the surface of a solid, the surface tension of the
liquid must be lower than the solid surface tension.
Contact Angle:
A useful measurement of the ability of a liquid to wet a surface is contact angle. Contact
angle is the angle between the solid surface and the tangent to the liquid surface at the angle of contact.
If the contact angle is greater than 90 degrees, the liquid tends to bead up. Liquids having contact angles
less than 90 degrees tend to wet surfaces. A contact angle of 0 degrees indicates a liquid will completely
cover a surface, while a contact angle of 180 degrees indicates the liquid beads up on a surface.
Dynamic Surface Tension:
The surface tension of inks and coatings on press do not necessarily stay
constant. The values can change during the printing process as ink splits from one surface and then wets
down another. The primary reason for this is the ink or coating is a mixture of various components, and
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during the dynamic printing process these components rearrange themselves every time the ink is split
and creates a new surface.
Most inks fall into the range of 25-40 dynes/cm. Obviously, the lower the surface tension
number, the better the surface wetting. However, since the ink is a mixture of components, during the
printing process these components change position due to ink splitting and need to reposition
themselves at the new ink/substrate interface. As the ink is split, a new ink surface is created, and the
ink's components must re-establish their positions with respect to the surface in contact.
Since the components of the ink or coating come in different sizes and shapes, they don't
re-establish their positions at the same speed. So, if a given surfactant is in the ink, its ability to reduce
the surface tension depends on how quickly it can reposition itself to reduce the surface tension. Not all
surfactants behave equally when it comes to this task. In general, the larger the molecule, the slower it
is to respond and the higher its dynamic surface tension.
Therefore, an ink can have a surface tension of 25 dynes/cm, but when it is subject to a
dynamic condition, such as a printing press, its “dynamic” surface tension behaves like it has a value of
40 dynes/cm. The faster the press speed, the more demanding is this effect on wettability and print
quality.
There are some separate techniques that are used to measure dynamic surface tension which are
different from those used to measure the normal surface tension of the inks. These will be mentioned
later in this report.
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Application: Parameters
Surface tension measurements are useful to predict surface wetting, however, they are not
the only criteria for good print acceptance or adhesion. Each printing, coating, or adhesive application is
unique and is affected by many process and material variables. Several factors may affect any individual
application.
Climatic Conditions:
Temperature and humidity affect how a solid and liquid interact. Surface wetting
characteristics may be significantly different winter to summer or dependent on
humidity.
Liquid Consideration:
High surface tension liquids have more difficulty wetting the surface of solids than
low surface tension liquids. Waterborne inks and coatings have higher surface
tensions than most solvent systems. Surfactants and solvents are useful in lowering
surface tensions.
The viscosity, drying time and solvency (“bite”) of the liquid will affect how an ink or
coating wets a surface. Changing the solvent in the ink or coating can improve
surface wetting.
Heating the ink or coating can favorably affect application.
It is important to remember that the surface tension of an ink, coating, or adhesive
must be lower than that of the surface to which it is applied to achieve good wet
out.
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Solid Considerations:
Surface tension is affected by material composition. Selection of plasticizer,
lubricants, stabilizer, and process aids contributes to surface tension.
Surface roughness can affect ink and coating wetting. Rougher surfaces allow ink
and coating “dive in” and promote mechanical bonding.
Moderate heating of the film can increase surface tension and receptivity.
Surface contamination or surface exudate will adversely affect ink and coating
acceptance. It is also important to consider sources of contamination which may
affect surface tension during printing and coating operations.
Surface tension of a solid surface must be higher than the liquid applied to achieve
acceptable wet out.
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Measurement.
Kibron DyneScan: high throughput screening of surface tension
The Kibron DyneScan performs high throughput screening of surface tension, the key
parameter determining the performance of ink.
Individual surface tension values of 96 samples (50 microliters each) can be measured in 2
to 20 minutes (depending on the application), allowing for truly cost-efficient high content screening of
ink samples.
Kibron Dynescan
The Kibron DyneScan comprises the use of the Kibron Delta-8 analyzer, DyneScan
software and a kit of Kibron 96-well Dyneplates, sensor Dyneprobes, and automatic cleaning
furnace Dyneclean.
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Kibron Delta-8
Basic features of Kibron Delta-8 are:
standard 96-well platform Dyneplates
sample volume only 50 microliters/well
simultaneous equilibration of 96 samples
measurement time of one plate 2 - 20 minutes, depending on the application
8 parallel high-precision microbalances and wire probes
automatic probe cleaning after each assay
integration possibility to robotics and automatic liquid handling systems
robust and compact construction
easy-to-use and minimal maintenance required
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Specifications of Delta-8 Analyzer.
The Delta-8 analyzer and Kibron Dyneplates are the platform for Kibron DyneScan.
Performance
Temperature range 18–30°C
Measurement volume 50 μl/well
Surface tension range 10-100 mN/m
Resolution 0.01 mN/m
Balance resolution 0.050 μgrams
Precision 0.2 mN/m
Method Maximum pull force/du Nouy
Measurement time (96-well plate) 3 minutes
Probe lifetime 100 plates
Cleaning of probes eClean (automatic Joule heating)
eClean cassette Lifetime 400 plates
DyneSearch - 96-well plates
Dimensions 127.8 × 85.5 mm (standard footprint)
Volume per well 50 μl
Type Disposable
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Software
Supported OS NT4.0 /2000/XP
Min. requirements PII266 MHz, 64 MB memory, CDROM-drive,
SVGA display, one free COM port, 25 MB disk space
Communication RS-232
Physical dimensions
Weight 24 kg / 52,911 lbs.
Height 405 mm / 15,945 in.
Width 770 mm / 30,315 in.
Depth 380 mm / 14,961 in.
Power supply
Input 100 –120/200 –240 V, 47– 63 Hz.
Output 12 V DC, 10.8 A.
Power max. 120 W
CE-approved
One INKscreen kit includes 100 Dyneplates, one cleaning furnace and 1 set of probes, allowing surface
tension measurement for 9600 samples.
The Kibron INKscreen is operated with dedicated and easy-to-use software for screening of surface
tension.
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Conclusion.
Surface tension determines the performance of inks
Surfactants are the key constituents in printing inks, their correct choice and concentration being critical
factors to product performance. There is currently an increasing demand to improve print quality on a
range of segments such as industrial inkjets, textiles, lithography, screen printing, and printing on more
diverse and complex media, including a variety of plastics.
High throughput determination of surface tension
The Kibron DyneScan allows for cost effective high throughput experimenting of a vast number of
surfactants and their combinations, yielding key parameters by which you can optimize and improve
your product formulations.
Surface tension can be measured 100 times faster compared to conventional methods, using a fraction
of sample material. Dynescan also allows measurement of 96 samples simultaneously and thus can
prove to be time saving when the workload is high.
The INKscreen allows you to reduce the design time of your products, reduce labor expenses and
material costs to facilitate early pipeline products. This all adds up to better products and
competitiveness.
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References.
1. Lloyds Research Foundation. Web. July-Aug. 2011. <•
http://www.lloydsresearch.com/pdf/All%20Product%20Leaflet.PDF>.
2. "Viscosity." The Physics Hypertextbook. Web. 05 Aug. 2011. <http://physics.info/viscosity/>.
3. Chemical Fabrics and Film. Web. 08 Aug. 2011.
<http://www.chemicalfabricsandfilm.com/research.html>.
4. "Some Things to Remember About Dynamic Surface Tension." Paper, Film & Foil Converter
Magazine | Converting Industry, Flexible Packaging, Slitting and Rewinding, Coating and
Laminating, Substrates, Synthetic Paper, Transdermal Patches, Atmospheric Plasma,
Coextrusion, Doctor Blade, Active Packaging. Web. 10 Aug. 2011. <http://pffc-
online.com/mag/paper_things_remember_dynamic/>.
5. Kibron DyneScan. Web. 12 Aug. 2011. <http://www.kibron.com/cmceeker/kibron-dynescan/>.