GRID Symposium 2012
Csaba Horváth, Rejtő Sándor
LEAN AND GREEN PRINTING… HIT OR MYTH?
Abstract:
On commission of a packaging printing company, the author has launched a research work in
order to find a methodology by which the necessary steps can be explored to turn the
application of this modern technology into a business success. The lean manufacturing studies
have primarily focused on the human–machine environment, analyzing all the activities that are
connected with the operation and servicing of the machines. Step by step, the research has
tried to expose those hindering factors, superfluous or less efficient organizational and
management process elements that now increase costs. Today, profitable printing production is
not feasible by means of price increases; the only expedient way to follow is to cut costs. In this
respect, lean management can be supportive.
Keywords:
lean printing, lean and green strategy, improving value chain performance,
Sustainability
Dragoljub Novaković, Igor Karlović
DRUPA AND POST DRUPA TRENDS IN GRAPHIC ARTS TECHNOLOGY IN THE TIME OF ECONOMIC CRISIS
Abstract:
The world still at financial crisis and many industries are trying to hold their positions. The
printing industry as a service industry especially in Europe was also severely hit by the
shrinking economy and aims to find new markets and possibilities in the changing world.
Drupa as the prime trend show for the graphic arts with shrinking attendances showed some
global megatrends and few surprises. Digitalization is a mega trend with possibilities to print
packaging, RFID tags and personalized low print run jobs. Digital printing systems mainly based
on electro photography and ink jet dominate the field while other sectors aim for maximizing the
efficiency and automation. The main attraction of Drupa was the Landa nanography technology
which promises some new ink application possibilities on a wide variety of substrates. This only
proves that innovation and technological breakthroughs are the main driving forces for
economical growth and problem solving. Also there is a clear trend of diversification of the
printing industry where the written words are more and more reproduced by the digital media
devices like tablets and on the other hand printing is used more and more for model making,
electronic circuit printing and even human body parts printing with 3D bio printers.
Keywords:
Drupa, nanography, digitalization, future trends
Miloje Đokić, Urška Kavčič, Matija Mraović, Matej Pivar, Leon Pavlovič, Tadeja Muck
PRINTED PASSIVE ELECTRONIC STRUCTURES ON RECYCLED PAPERS, CARDBOARDS AND FOILS
Abstract:
Printed electronics is expected to replace many conventional electronic systems. It is already
used in the manufacture of RFID tags, various sensors, OLED displays, batteries, solar cells
etc. The goal of printed electronic industry is to print electronic systems in roll-to-roll technology,
as cheap as possible.
Printed electronics can be divided into three parts: Wafer part, printed part and hybrid part.
Wafer technology is not classic printed electronics and it is characterised by the procedures
of production which are applied with the classic chip production (vacuum coating,
photolithography, etching, etc.) This technique has the possibility of designing high resolution so
that is applied in OLED displays, electroluminescent films, photovoltaic films, etc.
Printed electronics is based on the additive process of printing (flexo, screen, digital printing...)
where the various substrates were printed with functional inks. This type of printed electronics
can be fully printed by roll-to-roll technology that allows mass production, which significantly
affects the favorable price of products. Hybrid technology of printing electronics combines
the first two mentioned techniques. Flexible materials can be used with printed and
hybrid technology.
This research was focused on printing RFID antennas and sensors on recycled papers,
cardboards and foils. RFID (HF and UHF) antennas, humidity and temperature sensors were
printed with the semi-automatic screen printing machine. Monofilament polyester plain weave
mesh with 120 l/cm was used. These structures were printed using conductive (thermal
drying and UV drying) and dielectric inks and dried under hot air, UV and Heat&Press drying
conditions to obtain the lowest resistivity.
In the first part of our research UHF antenna was designed according to the chips specification
and printed. The radiation patterns of antennas were evaluated and finally the chips were
integrated onto the printed antennas to produce RFID tags. Measurements showed that tags on
all recycled papers and cardboards operate well.
The second part of our active research has already started. The humidity and temperature
sensors were printed and first analysis for humidity sensors were performed. Results
are optimistic.
Keywords:
HF, UHF, RFID, antenna, sensor, temperature, humidity, recycled paper,
cardboard, foil
Mojca Friškovec, Tina Mandelj, Špela Vasić Stepančič, Marta Klanjšek Gunde
THE INFLUENCE OF PHYSICAL PARAMETERS ON THE DYNAMIC COLOR OF THERMOCHROMIC PRINTING INKS
Abstract:
Thermochromic printing inks are different from conventional ones, since they change colour with
temperature. At low temperatures they appear in a coloured state but at high temperatures they
become transparent. The decolouration and the re-colouration don’t occur at the same
temperature; therefore the ink exhibits a colour hysteresis loop. For the development of
thermochromic inks and their use in precise applications, it is necessary to carefully analyse the
dependence of their dynamic colour on different extrinsic parameters which could influence the
colour response of the complex system inside functional pigment capsules. Research work was
focused on two commercial screen printing thermochromic inks. The dynamic colour was
characterized by five parameters – the total colour contrast, the openness and the width of the
colour hysteresis loop, yellowness and the area of the hysteresis loop described by the
corresponding colour change in the CIELAB colour space. The dependence of the parameters
on the layer thickness, the repeatability of the colour hysteresis loops of 3 consecutive heatingcooling
cycles and the influence of storage conditions of the sample prior to measurement were
studied. The results show that variation in ink film thickness has an effect on all parameters.
The starting temperature of the measurement can impact the colour hysteresis loop, i.e. if the
sample is firstly heated or cooled. The hysteresis loop in the first heating-cooling cycle in some
cases differs from those obtained in the second and third consecutive cycle. The analysis shows
that some parameters could influence the colour of thermochromic samples as a function of
temperature. These results are important for every advanced application of thermochromic inks.
Keywords:
thermochromism, thermochromic inks, hysteresis loop, dynamic colour, physical
parameters, characterization.
Silva König, Diana Gregor-Svetec
OPTICAL PROPERTIES AND UV/VIS SPECTRA OF AGED PAPERS
Abstract:
Change of optical properties is often the most obvious characteristic during paper ageing. The
decrease of brightness or the increase of yellowness occurs because of sunlight, high humidity
and high temperature. The moist heat and light treatments of accelerated ageing were applied
to investigate the ultraviolet/visible (UV/VIS) spectroscopy of non-recycled, recycled, uncoated
and coated papers. In addition to spectroscopy, the optical properties were measured to
evaluate cellulose and paper degradation. The results reveal different stability of aged papers.
The effect depends on the type of accelerated ageing and on paper characteristics.
Keywords:
recycled paper, accelerated ageing, moist heat treatment, light fastness, UV/VIS
spectroscopy, optical properties
Bohumil Jašúrek, Jan Vališ
UV/EB INKS AND VARNISHES IN PRINTING INDUSTRY
Abstract:
This paper reviews the different mechanisms of UV inks curing (free radical, cationic and hybrid
polymerization). The advantages and disadvantages of these various types of UV inks are
discussed together with their applications areas. Next, the various UV sources used for curing of
these inks are outlined. The text describes mercury lamps, doped mercury lamps, excimer
lasers and also UV LEDs. UV LEDs are potentially very interesting UV source, which may in the
future replace existing sources in some applications. The last part is focused on EB inks. In the
text the curing mechanism, applications areas and their comparison with UV inks are explained.
Keywords:
UV ink, EB ink, UV source, cationic polymerization, radical polymerization
Jelena Krstić, Jelena Kiurski, Dušanka Obadović, Ivana Oros, Miroslav Cvetinov
ABSORPTION CHARACTERISTICS OF MAGENTA SHEET-FED OFFSET PRINTING INK AS AN INDICATOR OF INK POLLUTION
Abstract:
The ultraviolet-visible spectroscopy was used to determine the absorption characteristics of
magenta sheet-fed offset printing ink. Two samples of printing ink, fresh and used, after 20,000
printed sheets, were investigated. The recorded spectrum showed the maximum absorption in
regions characteristic for Lithol Rubin B pigment. The intensity changes of the absorption
maximum is due to the energy shifts to lower values, while an increased band with occurs at
higher temperatures of printing processes associated with an increasing resonance energy. This
phenomenon could be useful as an indicator of ink ageing process.
Keywords:
UV-VIS, Lithol Rubine B, sheet-fed offset printing, pollution
Klemen Možina, Vera Rutar
MODIFYING NATURAL CaCO3 TO EFFECT ON QUALITY OF INK-JET PRINTS
Abstract:
Paper is the most common graphic material because of their traditional sustainability and
biodegradability. Coatings and surface treatment with natural components and additives can
replace unfriendly and more expensive synthetic materials, normally with special properties.
However, special properties can be obtained with surface functionalization by chemical or
surface geometry modification. Surface geometry modification can be achieved by the
application of the pigments and coating formulations with appropriate properties, granulation,
particle size distribution and particle shape. The ground calcium carbonate (i.e. GCC) usage in
papermaking industry is more and more widely used. Beside optical properties, the trends of
lightweight materials, i.e. reducing grammage by using nano materials and products (i.e. NMP),
lower specific energy requirement and costs, forces increasing of pigments usage. After all, as
everything has its own limits, the resemblance happens with GCC pigment. Following the stated
above, the pigment engineering appears with the idea of particles modification to increase its
applicability and particularity. Modified GCC particles, e.g. TCC (i.e. treated calcium carbonate)
enable wide range spectrum of the GCC raw material application. In the article, the right
technological procedure to treat wet grinded GCC and the effect on the changes of the particle
geometry, that at the same time, influence on increased functional properties, i.e. paper
structure and its surface are presented. Results of survey showed that properties of GCC
coated printing paper, required for ink-jet printing with water-based inks had improved.
Keywords:
GCC, modified pigments, coated paper, ink-jet printing, bleeding, wicking
Erzsébet Novotny, Rozália Szentgyörgyvölgyi
EXAMINATION OF NANOCOMPOSITES
Abstract:
Significant progress can be expected in the field of the production of high quality and varied
printed products thanks to nanotechnology, which exploits their new properties. Our work
focused on the measurement of the electric conductivity of nanocomposites. For the
experiments we prepared flexo inks with special composition, which contained multi-walled
carbon nanotubes. In the inks, we varied the % ratio of short and long nanotubes and the layer
thickness. According to the results of the examination the presence, length and percentile
distribution of nanotubes in the composite have a fundamental effect on conductivity. We also
analysed pictures of carbon nanotubes made with Genetic digital microscope and highresolution
CM10 transmission electron microscope. Due to their very strong density these inks
not need other black pigments.
Keywords:
nanotubes, nanocomposits, electric conductivity
Ondrej Panák, Tomáš Syrový, Linda Szőllősiová
PRODUCTION OF SECURITY PRINTING PATTERNS BY MEANS OF THERMOCHROMIC AND CONVENTIONAL OFFSET INKS
Abstract:
The aim of this work was to create patterns consisting of two parts. One part is a selected
combination of CMY frational area coverage with full overprint of thermochomic (TC) offset ink
and second part is a computed CMY simulation to match the first part in colour appearance. As
first, different binary combinations of C, M, Y were printed with overprint of TC ink with full area
coverage. The patches were measured by spectrophotometer to obtain reflectance spectra and
consequent colorimetric parameters. To be able to simulate the overprints with TC ink just by
CMY combination, simple colorimetric Neugebauer model, simple spectral Neugebaur model,
and also their Yule-Nielsen modifications were used. By iteration techniques, fractional area
coverage of CMY simulations was obtained. In second step, security patterns consisting of CMY
combination with TC ink overprint and their computed simulation were printed and evaluated in
terms of colour difference. For the study coated and uncoated paper and two TC inks (green
and red) were used. The results show, that spectral Neugebauer model with Yule-Nielsen
modification was in average the best predicting model in case of uncoated paper. The results
for coated paper show, that simulations computed by simple colorimetric Neugebauer model
resulted in lowest colour difference. However, the colour differences of simulations were above
4, regardless of computing method of CMY dot area coverage of the simulation.
Keywords:
thermochromic, Neugebauer model, colour simulation
Roberto Pashich, Snezana Andonovska, Aleksandar Markoski
CHANGES OF SPECTROPHOTOMETRIC CHARACTERISTICS ON OFFSET PRINTING SUBSTRATES UNDER THE EXTERNAL FACTORS INFLUENCE
Abstract:
Paper is the most used printing substrate which is subject of many external influences.
Hydrolytic degradation of cellulose molecules is the most often destructive process during the
paper natural aging. In this paper the spectrophotometric characteristics of four types of offset
printing substrates have been examined: Offset paper (70 gr/m2), Kunstdruck Matt (115 gr/m2),
Kunstdruck Matt (200 gr/m2) and Chromokarton (280 gr/m2). Test form is printed on KOMORI
SPICA 429P.
The analysis includes measuring of spectrophotometric characteristics of the mentioned printing
substrates after printing process, accelerated aging in thermal chamber with working controlled
conditions and repeated measurement of spectrophotometric characteristics of accelerated
aged prints.
Accelerated aging was performed in thermal chamber following the recommendations of ISO
5630 which provides chamber controlled conditions (temperature of 80 0C and 72 – 75 %
relative humidity). The intervals of accelerated aging are set of 6, 12 and 24 days. The
measurement was performed by spectrophotometer X-rite SpectroEye.
Keywords:
printing substrates, spectrophotometric characteristics, ISO 5630 - 3,
accelerated aging
Vesna Simendić, Nevena Vukić, Borislav Simendić
THE INFLUENCE OF PRINTING INKS VISCOSITY ON THE COLORIMETRIC PROPERTIES OF SCREEN PRINTED SAMPLES
Abstract:
The screen printing technique is different from other printing techniques, primarily because of its
simplicity and ability to print on substrates of any shape, size, material and thickness. Since
solvent-based inks are used in this technique, it is very important to reduce the level of volatile
compounds contained in solvents in order to protect the environment. This paper presents the
results of the influence of different viscosity values of screen printing inks on the colorimetric
properties of samples printed on plastic and ceramic substrates. Changing of viscosity was
determined by adding the solvent, and measured using a rotational viscometer. Inks were
printed on polycarbonate (PC) and ceramic substrates. Colorimetric properties of printed
samples were determined using the spectrophotometer Vipdens 2000. Since ink viscosity
directly depending on the amount of solvent, considering rheological properties, it is possible to
determine the minimum amount of solvent, without changing colorimetric properties of printed
samples. By determining the optimum amount of solvent in ink it is possible to avoid excessive
evaporation in the process of screen printing.
Keywords:
screen printing ink, volatile organic compounds, viscosity, colorimetry.
Tomáš Syrový, Michal Pál, Nikola Peřinka, Bohumil Jašúrek, Jan Vališ
ELECTRICAL PROPERTIES OF PRINTED CONDUCTIVE POLYMER LAYERS
Abstract:
The goal of this study was to evaluate the influence of several factors on electrical parameters
of printed conductive polymer PEDOT:PSS layers. The main factors studied were the
temperature conditions, the thickness of polymer PEDOT:PSS layers, the width of conducting
lines and contact arrangements of electrodes made by silver composite inks and carbon paste.
Prints were made on polymer substrate Melinex® ST 504.
Keywords:
PEDOT:PSS, screen printing, conductivity, sheet resistance
Jan Vališ, Bohumil Jašúrek, Ondrej Panák, Jitka Svobodová
DRYING OF UV AND HYBRID INKS AFTER INLINE VARNISHING
Abstract:
The aim of this study was to monitor drying of hybrid and UV curable offset printing inks with
additional UV varnish overlay. FTIR was used to monitor the curing of the inks and varnishes,
depending on UV dose (exposition time). Another considered parameter was the abrasion
resistance of ink layers depending on the time elapsed after press and irradiation.
Measurements were carried out on the varnished and unvarnished samples. Three different
substrates were used (cardboard, polymer foil and cardboard with metallic foil.
Keywords:
UV polymerization, abrasion resistance, FTIR
Tomislav Cigula, Jelena Poljak, Vedrana Peko, Tamara Tomašegović
SODIUM METASILICATE SOLUTION AS A DEVELOPER FOR CTCP OFFSET PRINTING PLATES
Abstract:
Many printing techniques increase their market share, but offset printing is still market leader in
printing of many graphic products. It is a very complex process in which printing plate has
significant influence on the final reproduction quality. Offset printing plates are in most cases
built of aluminium foils which are processed in order to enhance needed surface characteristics
and ensure stability and durability in the printing process.
One of the key processes in the plate making is developing which must remove ink receptive
photoactive layer, but in the same time minimizes change of the hydrophilic aluminium-oxide
layer. Therefore, chemistry free and low chemistry plates are being developed, but they are still
not used when it comes to the high quality products and reproduction of long runs, so
improvement of the chemical developing processes is of high importance.
This research was conducted in order to investigate application of developers based on the
sodium metasilicate of various concentrations. For that purpose samples of printing plates
coated with positive diazo photoactive layer were exposed in same condition and then
developed in developers with five different concentration of sodium metasilicate. Determination
of influence on the aluminium-oxide layer was made by observing profilometric roughness
parameters and the contact angel values when applying two different fountain solutions.
Results of the investigation have shown that concentration of the sodium metasilicate has an
impact on the aluminium-oxide roughness and consequently wetting properties, but comparing it
to the other investigated developers, the impact is smaller. Results have showed high
correlation between contact angle roughness parameters values, showing high influence of
surface structure on wetting properties.
This research has proved the influence of investigated developing process on the non-image
area surface, which could cause problems in printing plate exploitation. In addition, the sodium
metasilicate proved to be possible chemical compound to be used for developing of investigated
printing plate type, but prior to that there must be further research conducted to determine its
behaviour in other process parameters.
Keywords:
lithography, roughness parameters, contact angle, developing, sodium metasilicate
Sandra Dedijer, Tomislav Cigula, Dragoljub Novaković, Miroslav Gojo
THE CONTACT ANGLE OF REFERENCE LIQUIDS ON FLEXOGRAPHIC PRINTING PLATES AS A FUNCTION OF TIME
Abstract:
Wetting and spreading of a liquid on a solid surface are two surface phenomena which highly
influence many processes in various industrial fields. The wetting properties of the printing
areas on a printing plate have an important role in gaining high quality imprints since they
influence ink transfer from a printing plate onto the printing substrate. In flexography are that
properties even more important as the printing inks are of lower viscosity and the pressures in
the printing process are lower in comparison to the other printing techniques. Although wetting
properties could be observed by measuring static contact angle, the time dependant contact
angle is of high importance as time for the ink transfer from the anilox roller onto the printing
plate and finally to the printing substrate is very short. This paper shows results of determining
wetting characteristics of two flexographic printing plates by measuring the dynamic contact
angle of reference liquids and its influence on the surface free energy calculation. The obtained
results have shown that contact angle values of two reference liquids are slightly influenced by
the time of measurement, meaning they reach equilibrium state very fast. Furthermore, it could
be seen that printing plate type also influences the dynamic contact angle values. Surface free
energy of printing areas at investigated printing plates has not been significantly changed. This
research proved that time of the measurement has slight influence on the value of the contact
angle which means that reference liquids reach equilibrium state quickly and therefore surface
characterization of the flexographic printing plates could be made by observing only static
contact angle. On the other hand, when the most viscous liquid of the ones used (glycerol) was
applied on the surface, contact angle changed in time so further research should be directed to
determining the dynamic contact angle of the printing ink on the printing plate’s printing areas.
Keywords:
contact angle, wetting, surface free energy, flexographic printing plate
Tomislav Hudika, Tamara Tomašegović, Sanja Mahović Poljaček
OFFSET PRINTING PLATES: ALTERNATIVE METHOD FOR QUALITY CONTROL
Abstract:
In this paper the differences of results obtained by three measuring systems for determining
surface coverage value of the printing plates were presented. The aim of this research was the
introduction of image analysis as an alternative method for the characterization of surface
coverage and tone reproduction of printing plates. Results have shown that different measuring
systems for image analysis (IC Plate, ImageJ and Stream motion) obtain a different result in
coverage values calculation. IC Plate is automated device for capturing the printing plate’s area
and automatically calculating coverage value, while ImageJ and Stream motion are programs
supported by software which analyzes imported images that need to be captured by the
microscope. Based on the results, one can say that ImageJ and Stream motion are more
complex methods for coverage calculation, but they enable greater control of the imported
images by means of manual adjustment.
Keywords:
printing plates, image analysis, quality control
Sanja Mahović Poljaček, Tamara Tomašegović, Miroslav Gojo
INFLUENCE OF UV EXPOSURE ON THE SURFACE AND MECHANICAL PROPERTIES OF FLEXOGRAPHIC PRINTING PLATE
Abstract:
Flexographic printing plates are widely used in packaging printing and are therefore a subject of
number of studies. Since the properties of the flexographic printing plate significantly
influence properties of the final product, the impact of different plate processing conditions were
investigated in this paper.
Samples of flexographic printing plate used in this research were made form liquid
photopolymer, and the influence of main exposure (UV radiation) on mechanical and physicalchemical
properties was studied. Contact angle, surface energy and hardness changes were
measured. Information about changes that occur on the surface and in the volume of a
flexographic printing plate as a result of different processing conditions was provided. Results
obtained in this paper are relevant for the flexographic reproduction process for two reasons:
they point to the absorption of the printing ink and they define possible deformations that occur
due to the pressure in printing process.
Keywords:
flexography, photopolymer, UV radiation, hardness, contact angle, surface energy
Neda Milić, Sandra Dedijer, Magdolna Pal, Živko Pavlović
THE STATISTICAL ANALYSIS OF PROCESSING CONDITIONS' INFLUENCE ON THE SURFACE ROUGHNESS OF FLEXO PRINTING PLATE
Abstract:
The ink transfer from the flexo printing plate to the printing substrate, which determines the
quality of imprints, is highly influenced by the surface topography of printing plate. The aim of
study was to investigate the correlation between roughness characteristics of solid printing
areas and different plate processing conditions. For this purpose, eight samples of CtP flexo
plate with thermal developing were made varying two factors: the main exposure time (8, 10, 12
and 14 minutes) and the number of rotations of developing drum (8 and 10 rotations).
For comparing roughness parameters from all eight plates, a two-factorial ANOVA was applied.
Since obtained results showed the significant main effect of exposure time, but also the
interactive (join) effect of two factors, for the further analysis of the separate influences onefactorial ANOVA and T tests were used. Discovered significant influence on the surface
roughness of the printing plate implies the importance of specifying and monitoring values of
investigated processing conditions.
Keywords:
flexo printing plate, surface roughness, statistical analysis, processing conditions
Petra Balaban
THE SIGNIFICANCE OF COLOUR AND ITS COLOUR CHARACTERISTICS ON PRINTED FLEXIBLE PACKAGING
Abstract:
This paper is a segment of multiple criteria study of flexible printed packaging. Its value is
affected, among others, by non-verbal criteria (colour, size, material, shape, image, graphics).
Those criteria have a major impact on making decisions when buying any packaged product.
The overall quality of print is greatly influenced by colour characteristics.
This paper deals with subjective assessment of those characteristics and influence of printing
inks viscosity and speed on colour variations in polymer packaging foils (polyethylene,
polypropylene).The study was carried out in a local printing office mostly producing packaging
for granary and powdery foodstuffs.The study revealed colour variations of prints at different
viscosity and speed.
However, the issue here is different subjective assessment of colour characteristics within the rest
of requirements for flexible packaging by producers, byers and the author of this paper respectively.
Keywords:
flexographic printing, packaging foils, colour characteristics
Zoran Gazibarić, Predrag Živković, Dragana Živojinović
DETERMINING THE CORRELATION BETWEEN TOTAL HARDNESS OF WATER AND SPECTRO-DENSITOMETRIC CHARACTERISTIC OF PRINTING QUALITY
Abstract:
The wetting solution plays significant role in offset printing process, helping in separation of
printing from non-printing areas of the printing form. The wetting solution is characterized by the
share of isopropyl alcohol, pH value, electrical conductivity, temperature and water hardness,
which is a direct consequence of the presence of various salts in water.
It is proved that setting the optimal total hardness of water, which is recommended to be kept
from 8od to 12od of German hardness, could extend the service life of metal components and
machine parts in contact with the wetting solution, because of reduced corrosion and lime scale
sedimentation. It also extends the life of the rubber rollers in contact with the wetting solution.
However, there is an issue of particular owner’s and management’s interest: would they get
prints of higher quality if they install system for regulation of the water hardness?
In this paper an attempt was made to determine the correlation between the total hardness of
water and some characteristics of print quality (tone value increase, range of reproduced tonal
values, maximum screen ruling at which it is possible to get a clear image without defects).
In the experimental part a single color sheet fed offset printing machine will be used, on which
all printing conditions will be kept constant, except the hardness of water to be used in the
wetting solution. Soft, medium hard and hard water will be used.
Keywords:
wetting solution, water hardness, print quality
Nemanja Kašiković, Gojko Vladić, Neda Milić, Darko Avramović
INFLUENCE OF INK LAYERS AND DIFFERENT MATERIALS ON THE COLOUR FASTNESS TO RUBBING
Abstract:
Textile materials printed with screen or digital printing during the exploitation can be under the
influence of various environmental elements and treatments. This paper presents research
regarding influence of ink layers and different type of materials on colour fastness to rubbing.
Research was done on three different types of textile materials composed of 100 % polyester.
Test chart consisted of four colour fields each 100% of one of process colours (CMYK) and was
printed on substrates. Printing machine Mimaki JV22-160 with J-eco Subly nano inks was used.
Apart from substrates, variable factor was number of ink layers applied, textile materials were
printed with one, two, three, four and five layers of ink. The analysis of rubbing treatment
influence on prints was done according to ISO 105-X12 standard. Total of 120 samples were
analyzed. Resistance of colour to rubbing treatment (dry and wet staining) was determined by
usage of the grey scale.
Keywords:
ink layer, type of materials, polyester, rubbing, ink jet
Mladen Stančić, Igor Karlović, Ivana Jurič
INFLUENCE OF DIGITALLY PRINTED SELF ADHESIVE FOILS ON PRINT QUALITY PARAMETERS
Abstract:
Printing substrate and its characteristics has a significant impact on print quality. Essential
characteristic of substrates is the substrate surface. Substrates with different surface have
various reflection of light, which leads to various print quality. Print quality itself is a complex
term that includes desired colour reproduction and satisfactory reproduction of image elements.
Important print quality attributes are sharpness, mottle and line quality. In this paper we have
focused on ink-jet printed PVC self adhesive substrates. Three PVC substrates (enlightened
and nonenlightened) have been measured and based on image analysis it can be concluded
that the substrate surface and enlightening affects the print quality.
Keywords:
print quality, modulation transfer function (MTF), mottle, line perimeter, line area
Rozália Szentgyörgyvölgyi, Rejtő Sándor
PRINTING OF FOLDING CARTON BY DIGITAL TECHNOLOGIES
Abstract:
The market share of the digitally printed packaging materials in the world is in constant rise. The
reason for this is the rapid improvement of the quality and efficiency of these printing
technologies, as well the increase in demand of small print run packaging by the producers.
In this paper we have researched prints made with electro photographic and inkjet which were
made on cardboard substrates. Four different cardboard substrates which differed in surface
properties were printed with Xerox Docucolor 12, Xerox iGen3, Canon ImagePress C1 and
Canon Pixma iX6550. On the prints we have measured the optical properties (TVI, ΔE*ab,
reproducible gamut). The largest TVI on all cardboards was found with the Canon Pixma iX6550
inkjet printer and also the largest colour offsets were measured on these samples. The
reference for the samples was the ISO 12647/2: 2004. The smallest colour difference was
achieved on Canon ImagePress C1 electro photographic prints while the largest colour
difference was measured on the prints made by Canon Pixma iX6550 inkjet printer.
Keywords:
folding carton, electro photography, inkjet, colour gamut
Agić, D., Rudolf, M., Agić, A., Stanić-Loknar, N.
CASE STUDY CARBON BLACK SEPARATION EXTENDED FEATURES
Abstract:
Case study in work is determining extended black separation in current graphic arts, in infra red
properties. Graphic reproduction is generally based on screening system, principles of
subtractive synthesis and separation with mostly added black, with infrared Z absorption.
Subtractive ternary color combinations could be partially substituted with black, that can lead to
achromatic way of reproduction, with various extended possibilities. The aim is to prove stability
of achromatic system, and operating in NIR domain, as wide acceptance is desirable.
Keywords:
subtractive, carbon black separation, achromatic, NIR
Ana Gebeješ, Ivana Tomić, Rafael Huertas, Mladen Stepanić
A PRELIMINARY PERCEPTUAL SCALE FOR TEXTURE FEATURE PARAMETERS
Abstract:
Texture, along with colour, is one of the most important characteristics of a material defining the
appearance of its surface. While colour had been studied for a long time and continues being a
hot topic, the analysis of texture has traditionally been postponed. However, in the last years
texture is being more and more considered, for example in image analysis and processing to
detect regions of interest in images or recognize objects. In the fields of image analysis and
processing different ways to manage texture are proposed, where almost all of them are based
on the so called texture features computed from the image. The following parameters,
describing some of the texture features, are the most widely used: Contrast, Homogeneity,
Dissimilarity, Energy and Entropy. If these parameters characterize a texture, then they must be
related with the perceived sensation texture produce. The aim of this paper is to perform a
preliminary visual experiment in order to scale each of these parameters according to human
texture perception. The five above parameters are computed for 10 greyscale images, which
differ in their texture strength. The obtained values are then correlated with the results of the
perceptual test, indicating the scale and the applicability of these parameters in describing
texture perception.
Keywords:
texture, image analysis, perceptual scale
Ivana Jurič, Igor Karlović, Ivana Tomić
THE POSSIBILITY OF USING G7 METHOD FOR CALIBRATION AND CHARACTERIZATION OF XEROX DOCUCOLOR DIGITAL PRESS
Abstract:
G7 method introduces gray balance control as the key to achieve consistent colour
reproduction, instead of controlling optical density and tone value increase (TVI). This method
was originally intended for commercial offset printing, but it is also applicable to virtually any
CMYK imaging process and has been successfully tested on a wide range of processes,
including coated and uncoated offset, newsprint, gravure, flexography, digital printing, as well as
a wide range of AM and FM screening methods.
This study is focused on the validation and efficiency of G7 method in calibrating Xerox
DocuColor 252 digital press that is based on electrophotographic process. By following the
guidelines of G7, the quality of gray and colour reproduction was compared to factory
calibration. The results indicate the need to make additional adjustments in addition to the basic
G7 method. G7 method alone is not sufficient to calibrate the toner based printing press.
Keywords:
G7 calibration method, gray balance, digital press
Krisztián Samu, Zsuzsanna Veres
COMPARISON OF INDUSTRIAL AND NON AUTOMATED COLOR CALIBRATION CREATED COLOR PROFILES
Abstract:
To use color management systems the condition is to useappropriate color profiles to the device.
There are two ways to get to these appropriate color profiles. We can use industrial color profiles
or we can create our own color profiles by color calibration. The great advantage of the industrial
profiles is the easy access, however arising from manufacturing and other uncertainties these
reliability is in question. Creating our own color profiles is lengthy and requiring expertise and even
this is no guarantee of perfect color profile, because during the calibration we can make different
types of measurement errors. These errors can be significant mainly in the case of manual (non
automated) calibration. In this paper, the question we would like to provide answer is that
industrial or non automated calibration should we use to an inkjet printer?
Keywords:
ICC color management, inkjet printing, color measurement
Gojko Vladić, Nemanja Kašiković, Drako Avramović, Neda Milić
COLOR DIFFERENCES OF PROCESS COLORS AS PREDICTORS OF SECONDARY MIXTURES, RED, GREEN, AND BLUE IN DIGITAL TEXTILE PRINTING
Abstract:
Color printing of textile is achieved by subtractive color mixing of four process colors cyan,
magenta, yellow, and key (black), also called CMYK color model. Real textile products are
usually colored by wide variety of colors achieved by mixing of the process colors. The process
colors are not often used in pure form. Great majority of research regarding the color of textile
products and various influences on the color is dealing with process colors; therefore it is
needed to gain insight in correlation between results for color differences of process colors and
colors in real application. This paper focuses on correlation between color differences of
process colors and secondary mixtures, red, green, and blue varying textile substrates in digital
textile printing. Four different materials were printed with pure process colors and their mixtures
using printing machine Mimaki JV22-160 with J-eco Subly nano inks, colors were measured and
differences calculated. Comparison was made between color differences of process colors and
their mixtures. The results of the research show strong correlation between color differences, it
can be concluded that results of research on process colors can be good predictors for other
colors achieved by mixing the process colors, although some inconsistencies were noticed and
require further investigation.
Keywords:
textile printing, color differences, process color, color mixtures
Darko Avramović, Nemanja Kašiković, Gojko Vladić, Željko Zeljković
HTML5 AND SVG DRIVEN METHODS FOR DATA PRESENTATION IN SCIENTIFIC PUBLISHING
Abstract:
This paper proposes certain methods of displaying scientific results to public. Instead of
common data carrier format types like Adobe PDF, HTML5 and SVG offer alternative way of
graphic presentation of data. The paper shall present methods of generating dynamic graphs,
plots, color palettes and other sorts of graphic objects used for displaying science results.
Nevertheless, performance tests were conducted to determine common browsers performances
while creating such objects. Individual and mixed objects patterns were used. The browsers ran
inside specially created test environment including dedicated chamber application for
performance measurements. The data gathered was statistically processed and based on that
conclusions were made.
Keywords:
html5, svg, graphics, browser, performance
Vivien Bareis, Iryna Artemieva, Barbara Dörsam, Thomas Hoffmann-Walbeck
JDF-PDF PREFLIGHT SOFTWARE
Abstract:
Software is presented that analyses inconsistencies in the definition of trim boxes and bleed
boxes for a job. For that the PDF-file and the related JDF-file are examined.
Keywords:
Preflight, PDF, JDF, Trim box, Bleed box
Aleš Hladnik
DIGITAL IMAGE COMPRESSION USING PRINCIPAL COMPONENTS ANALYSIS
Abstract:
Data compression plays a crucial role in various modern digital photography and video
applications. Its main goal is to reduce irrelevant and/or redundant image data while keeping
relevant information intact as much as possible. There are numerous international as well as
industry standards available that are based on either lossless or lossy compression of images.
While a lossy compression standard such as JPEG offers a tradeoff between the image
quality and the file size, in lossless compression methods – run length encoding, LZW, Chain
codes and others – no information reduction takes place, but the image file size may be
prohibitively large.
Principal components analysis (PCA) is an established multivariate statistical tool that linearly
transforms a number of possibly correlated variables into a smaller number of new variables,
known as principal components. Since a digital image can be regarded as a two – or more –
dimensional function of pixel values and represented as a 2D (grayscale image) or 3D (color
image) data array, PCA can be performed on such an m x n matrix. The presentation will
demonstrate how to implement PCA for image compression on different digital images and, in
particular, how the choice of the number of extracted PCs affects the image compression ratio
and consequently the image quality.
Keywords:
Principal components analysis, image compression, digital image processing
Andrej Iskra, Klemen Možina
ANALYZING DIFFERENT ELEMENTS OF WEB GALLERIES
Abstract:
Web galleries are one of most used elements of web sites. They are framework for presenting
images. Images are very important elements in web sites in the sense of carrying information.
Good images show concepts, carry information, invoke positive fillings, etc. All this aspects
contribute to positive user experience. On the other hand, bad images waste space, are usually
ignored, or even worse, are confusing for the users. Images in web galleries can have additional
elements, like image index and image captions. Index helps users to realize the size of the web
gallery and where they are at certain image. Image captions increase informational value of the
images. In this study we tested three web galleries with different combination of these additional
elements. Testing was performed with eye tracking system. Eye tracking technology allows us
to analyze how people look and use certain test form (i.e. web gallery). We can also create AOI
(area of interest), which was, in our case, used in research of image index and image captions.
Keywords:
web galleries, image index, image captions, eye tracking, area of interest
Vladimir Zorić, Branko Milosavljević
DIGITAL PUBLISHING FORMATS
Abstract:
In recent years the Internet has become the main source of information. The increasing
presence of wireless signal transfer allows us to via mobile devices: smartphone or tablet
device, get the information immediately. The viewing and manipulation of these informations are
possible with the use of different software and document formats. One such format is EPUB.
EPUB is the format used for viewing and manipulating electronic publications. This format is
stan dardized by the organization called IDPF. In 2011, IDPF presented the third improved
version of the EPUB. This format beside text can contain meta data, audio and video recording,
linking, and other multimedia forms. This format offers a completely new understanding of
learning, reading books, magazines, daily news.
The increasing environmental awareness, economic aspects, the emergence of mobile
devices, access to information, the ability to manipulate, enables that digital publishing gets
used by the wider public and business users. Publishing today includes not only printing and
publishing books, magazines and other publishing material, but publishing all them also in some
digital form.
Keywords:
IDPF, EPUB, digital publishing, tablet devices, software, Internet
Uroš Nedeljković, Bojan Banjanin, Irma Puškarević, Ivan Pinćjer
EMPIRICAL FINDINGS ON FEATURE DISTINCTIVENESS: LEGIBILITY BASED ON DIFFERENTIATION OF CHARACTERS
Abstract:
After a series of empirical findings from the first half of the last century, and a stream of
empirical findings in the field of legibility and readability of typefaces, little research has
sustained a grounding theory. Since the majority of psychologists do not possess sufficient
knowledge of typography, their studies lacked internal validity (Lund, 1999), whereas
typography scholars have published numerous ungrounded work in their attempt to base the
discourse stylistically and ideologically. Seen from our hindsight, providing the theoretical
framework for this field was less probable without the cognitive information processing theory.
Numerous research regarding word superiority effect support different hypothesis (Cattell, 1886;
Reicher, 1969; Wheeler, 1970; McClelland & Johnston, 1977)) but only with the advancement of
the eye tracking and the neural network modeling in the '80s scholars were able to obtain
precise answers to the question: How we recognize words? (Rayner & Pollatsek, 1989;
McClelland & Rumelhart, 1981; Seidenberg & McClelland, 1989).The findings that the bottomup
processing in parallel distribution (PDP) starts from feature level indicates that if we want to
progress the legibility of the typeface we need to explore the feature level ie. feature
distinctiveness. Therefore, this paper analyzes key findings on legibility of letters within type
which have been perceived as meaningful for designers and type practitioner.
Keywords:
legibility, feature, distinctivnes, typefaces
Slobodan Nedeljković, Ivan Pinćjer, Uroš Nedeljković
PRINCIPLES OF ART NOUVEAU AND IT'S REFLECTION ON CONTEMPORARY TYPE FORMS
Abstract:
This paper analyzes the new Art Nouveau typeface by Slobodan Nedeljković - Zaharius Neo-
Secession. It is very difficult to determine weather this typeface follows the continuity of this
typographic form, or is it a hybrid sub-form of some kind. Therefore, it is necessary to look
back at some of the influential classical typefaces, such as Schwabacher, Behrens and Fette
Eckmann whose authors have instilled them with a personal touch corresponding to the
period in which they had been designed. Neo-secession type forms are celebrating its 100th
birthday, but it is evident that this style holds up extremely well, because of both its artistic
and functional appearance. This paper studies the Jugendstil groups and their specific
characteristics that have made way for interpretations by new authors, as well as the process
of designing a typeface and its morphological development. Finally, we have considered the
typographic characteristics and the practical applications according to the latent, dynamic
rhetoric of our new typeface.
Keywords:
Neo-Secession, Fractur, Hybrid typeface
Nace Pušnik, Klementina Možina, Anja Podlesek
COMPARISON OF PROCESSING WORDS PRESENTED AT VARIOUS POSITIONS ON DISPLAY
Abstract:
Television production of broadcasts is developing. Graphic design is mainly based on previous
(successful) broadcasts. In many cases, this is the correct procedure, but it can lead to the loss
of design diversity. Inverse colour combination is an aspect that should be integrated into
television design, as darker colours for backgrounds make lighter colours of typeface more
visible and for this reason easier to read and remember. In the present study, we examined if
the positioning of the text on a display is also important. Various meaningful and meaningless
three- and five-letter words were set in the Bank Gothic typeface. Words were presented at four
different positions on the television screen (in four corners of the screen) for a short time, with
the presentation intervals ranging from 240 to 360 ms. To compare various technologies that
are available in the market, we also varied picture size to assess the contribution of display size
on the speed of word processing. Results showed that the left side of the television display was
more convenient for users, regardless of upper or lower position. However, variations between
upper and lower position were obtained for the right side of the display. When placed to the left
side of the display, use of three- and five-letter meaningful and meaningless words did not affect
visibility or legibility and recognition of words. We conclude that placing titles to the left side may lead to better title intelligibility.
Keywords:
broadcasting, legibility, duration, position, display.
Radoš Radivojević, Sonja Pejić
COMMUNICATION THROUGH DESIGN: TRANSFER OF IDEAS - CREATION OF CONTEXT
Abstract:
In order for something to be understood it does not have to be said. An image that provides
information on surroundings, which is simultaneously an idea being realized and an idea that is
going to become materialized, is just enough. Coding of ideas, information and attitudes by
using commonly accepted patters, styles and models that are interesting enough to draw
attention, represents new form of communication in the era of virtual society. Design is a
medium through which an idea or object is sent, but it is also a medium which becomes the
message. This paper problematizes the possibility of a successful transfer of ideas by means of
design, as well as the limits of perception of visual contents. Since design is one of the factors
that affects the shape of social reality and contexts, it raises the question of whether reality
created by design is a real manifestation of artist’s idea or it distorts the initial ideas of its creator
when in contact with socio-cultural factors of society.
Keywords:
design, medium, message, virtual society.
Savka Adamović, Ljiljana Rajić, Miljana Prica, Rastko Milošević, Irma Puškarević, Vladimir Zorić
ELECTROCOAGULATION/ELECTROFLOTATION TREATMENT OF OFFSET PRINTING DEVELOPERS
Abstract:
In this study we investigated the electrocoagulation/electroflotation as a purification treatment of
fresh and waste offset printing developers. Electrochemical treatment was studied in a
bipolar batch reactor with four plate aluminum electrodes at a constant distance of
0.5 cm. Electrocoagulation/electroflotation process was carried out at a current density of
2 mA cm-2. Temperature, pH and electrical conductivity were measured before and after
electrocoagulation/electroflotation treatment, while the content of organic substances in terms
of UV813 and turbidity was used to evaluate treatment efficiency.The results indicated
electrocoagulation/electroflotation as reliable, safe and cost effective method that can be
successfully applied to treating fresh and waste offset printing developers.
Keywords:
-
Diana Milčić, Davor Donevski, Mladen Šefer
ASSESSING PRINT PRODUCTION PROCESS CAPABILITY
Abstract:
Process capability refers to the proportion of units conforming to specification that a process is
able to produce. In print production, process control standards specify aimed and tolerance
values for specific process control parameters. However, producers and customers have to
agree on the acceptable quality level (AQL), i.e. tolerated proportion of nonconforming units. In
order to agree on the AQL, the producer has to know the capability of his process. In addition,
process capability can be determined in a number of different ways, depending on how the data
is collected and analyzed. The experiment presented in this paper shows how different ways of
data analysis affect the assessed process capability. In order to avoid confusions and
arguments between producers and customers, it is necessary to agree on the way of data
analysis (determination of proportion of waste). This part is not covered by process control
standards as they can only serve to determine whether a given unit conforms to them or not.
Keywords:
print production, process capability, process control
Rastko Milošević
MECHANICAL MODELS FOR CREASING AND FOLDING BEHAVIOUR OF PAPERBOARD AND CARDBOARD: STATE-OF-THE-ART
Abstract:
During the process of paperboard and cardboard converting, the board’s top ply can break as it
folds. To prevent this from happening and to prepare the material for folding, the process of
creasing is applied, which defines folding lines and deforms the material plastically. Thus, some
delamination occurs in the creasing zone, as a result of which paper plies bend inwards during
folding and, therefore, the top ply is not stretched to its failure. There are a few criteria that
define a good quality crease: the shape of a creasing zone and the existence of a bending
moment-angle curve peak, which must occur before a certain angle is reached. The aim of this
paper is to give better understanding and deeper insight into different behaviour of paperboard
and cardboard materials during creasing and folding processes. The existing mechanical
models for creasing and folding behaviour of these materials are surveyed. Comparisons of the
related testing methods are made as well as the assessment of the levels of their reliability. The
mechanical models discussed are categorized with respect to its accuracy, complexity and
materials on which they can be applied.
Keywords:
mechanical models, creasing, folding, paperboard, cardboard
Magdolna Pál, László Koltai, Dragoljub Novaković, Sandra Dedijer, Srđan Draganov
CHARACTERISATION OF FOLD-CRACK RESISTANCE OF COATED PAPERS BY TENSILE AND MULLEN BURST TEST
Abstract:
The folding process is usually resulting in more or less visible cracks along the folding line on
the outer side of the coated papers and boards. The basic mechanism of cracking is laying in
the appearance of higher stresses on the surface layers when a sheet is folded. These high
stresses can lead not only to decrease of the aesthetic feature, but to complete loss of
functionality of the final product. Improving the fold-crack resistance of coated papers and
boards is one of the basic tasks for paper manufacturers. This study has been conducted in
order to analyze the correlation between two basic physical parameters of the folded coated
paper: residual tensile strength and bursting strength. The residual tensile strength testing is
one of the most commonly used fold-crack resistance testing methods, but since the specimens
during the bursting strength testing have curved configuration, the bursting strength of unfolded
and folded coated papers may provide additional relevant information about stress states on the
outer layers of the paper.
Keywords:
coated papers, fold-crack resistance, residual tensile strength, bursting strength
Miljana Prica, Božo Dalmacija, Vesna Pešić, Rastko Milošević, Bojan Banjanin, Vladimir Zorić, Savka Adamović
POSSIBILITY OF USING CARDBOARD MILL SLUDGE IN IMMOBILIZATION OF COPPER FROM CONTAMINATED SEDIMENT
Abstract:
Pulp, paper and cardboard mills typically generate significant quantities of non-hazardous
solidwaste which requires management as a waste material or as a by-product. Most of these
solids are removed after primary mechanical treatment, resulting in a sludge that contains large
quantities of fibers, papermaking fillers, or both. Although this primary sludge is commonly
landfilled, it could be recycled into on-site production, reused in other pulp and paper mills, or
used in other products. In this study the use of cardboard mill sludge as stabilizing agent in the
stabilization treatment of copper polluted sediment was examined. Semi-dynamic leaching test
was conducted to assess the effectiveness of stabilization treatment with cardboard mill sludge
and long-term leaching behavior of copper. A diffusion-based model was used to elucidate the
controlling leaching mechanisms. It appears applied treatment was effective in immobilizing
copper, with diffusion being the controlling mechanism. This indicates that slow leaching of Cu
could be expected when the cardboard mill sludge as stabilizing agent was applied.
Keywords:
copper, cardboard mill, sludge, contaminated sediment