sublimation print for textile material
TRANSCRIPT
98 SCREEN PRINT INDIA - July 2011
Colour is something, which makes the object more appealing, attractive and gives the pleasure of observation. The desire to create garments and other artefacts that refl ect the beauty of the world around us and provide for the expression of artistic nature has been evident from early in human history. Textile materials like fabric and garment can be coloured in two ways either by dyeing or printing. Dyeing is colouring the fabric or garment with the single color and printing is applying coloured patterns and designs to decorate a fi nished fabric. Textile printing is the most versatile and important of the methods used for introducing colour and design to textile fabrics. Textile printing requires the correct coordination between the printing machinery support and the human skill for producing the best of the results. Textile printing uses various printing techniques like, Screen, block, ink jet, hand, block, tie and die, kalamkari, batik, while garment printing can be done by Plastizol, Fluorescent, Metallic, Puff, Foil printing apart from above textile printing. Several techniques have been are in use and the colorants available have multiplied, the
Sublimation Print for Textile MaterialTextile printing requires the correct coordination between the printing machinery support and the human skill for producing the best of the results, says Vasant R. Kothari
latest and the most popular is Sublimation
Print for Textile Materials.
Dye sublimation printing work under the
process of sublimation, so it is necessary
to understand sublimation to understand
the dye sublimation printing process. We
have learnt in Chemistry that an element or
compound normally has 3 states viz. solid,
liquid and gaseous state and conversion from
one state to another can happen by applying
heat (solid >> liquid >> gaseous) or by
removing heat (gaseous >> liquid >> solid).
See Fig. 1.
Process
The technology works primarily on polyester
and special polyester coatings applied to
the surface of an object. Sublimation works
by dying the fabric with colour, allowing
the fabrics natural wicking properties to be
maintained. At high temperatures, the solid
dye converts into a gas without ever becoming
a liquid. The same high temperature opens
the pores of the polyester fabric and allows
the gas to enter. When the temperature
drops, the pores close and the gas reverts
to a solid state. It has now become a part
Technology
Fig 1 : The nomenclature for
different phase transitions
Fig 2
SCREEN PRINT INDIA - July 2011 99
of the fabric, meaning there is no chance
of colours bleeding, or washing out, and
one of the biggest advantages over 'screen
printing' and other processes. The only way
they are going to come out is possibly if
fabric is kept in the sun for the next two
or three years but then the material will
probably sun rot before the dyes go away.
Dye particles that are used for this type of
dye sublimation are designed to only bond
with polymers, so the higher the polyester
content in the material the more dye that will bond giving a brighter image. This is why dye sublimation can’t be done on natural materials, such as 100% cotton. Natural fi bers and noncoated materials which have no 'pores' to open cannot
accept the gas vapor. The dye particles
are designed to bond with polyester, and
ignore everything else. It is like trying to mix
oil and water with most natural materials.
Out of all of other printing methods, dye sub
is the most eco-friendly
Dye sublimation will produce fantastic
color on white and light colored fabrics.
The technology is perfect for high-margin
customization, certain sporting uniforms
or jerseys, performance apparel or any
application where photo-realistic images are
needed and durability a top priority.
Direct & Transfer
Dye Sublimation can be applied on the fabric
in two different ways either directly on fabric,
i.e. direct print or fi rst on the paper and then
on fabric i.e. transfer print
Transfer Dye Sublimation Print
The images are initially printed on coated
transfer paper as a reverse image of the fi nal
design. The paper is then placed on the pre-
cut polyester fabric pattern and both are
placed into a heat press. When the heating
cycle is completed, under high temperature
and pressure, the dye turns into a gas and
permeates the fabric and then solidifi es into
its fi bers, the image on the paper has been
transferred to the item and has actually
reformed into or underneath the surface.
The fabric is permanently dyed so it can be
washed without damaging the quality of
image. See Fig. 3 and Fig. 4.
Direct Dye Sublimation Print
The images are directly
printed on treated
polyester fabrics, which
are then heated by heat-
fi xation devise that fi xes
the color on the fabrics.
This method eliminates
Dye particles that are used for this type of dye sublimation are designed to only bond with polymers, so the higher the polyester content in the material the more dye that will bond giving a brighter image. This is why dye sublimation can’t be done on natural materials, such as 100% cotton.
Fig 3 : Process fl ow of Transfer Dye Sublimation Print
Fig 4 Process fl ow of Transfer Dye Sublimation Print
100 SCREEN PRINT INDIA - July 2011
the need for
transfer papers.
This means no
paper cockling
and reduction
in defects such
as ghosting and
various wave or
tiger stripes that
are common in
roll-to-roll transfer
printing. This
type needs an ink
waste pit to collect
excess ink and prevents it from staining the
reverse side of the fabric. See Fig. 5.
Starch is coated on fabrics to avoid blur or bleeding of ink Print directly on pre-treated fabrics Non-contact heater fi xes color on the fabrics. See Fig. 6.
Method of selection
Dye sublimation transfer is relatively old as compare to direct dye sublimation and hence has a big market share. Both methods have their own advantages and disadvantages and the selection is purely based on the customer requirement, the type and quality of output required. Transfer yields higher quality and direct yields higher productivity.
The typical viewing distance of print is
again one of the most important factors to
determine which method to go with. Close-
up viewing with high-resolution requirements
on knit fabrics, normally used in sportswear,
would lead to paper transfer which gives the
most saturated color and crisp line detail as
compare to direct print. Further, in case of
panel printing transfer print is more suitable
as the prints are small in size and placement
of print design is of prime importance which
can be comfortably achieve with the help of
transfer print.
Direct printing gives less resolution and
suitable for distance viewing. So it is widely
used for the industrial purpose like home
furnishing, curtains, banners, and signage.
Another advantage is the production rate
which reduces the total production cost in
terms of longer length fabric.
Applications
Dye sublimation is perfect for printing to a
wide range of manmade and mixed content
textiles including :
Whether it is a printing a repeated textile
pattern design to be incorporated into a
garment, creating cushions, curtains, banners
and much, much more, the process of dye
Technology
Fig 5 : Process Flow of Direct Dye Sublimation Print
Fig 6 : Process Flow of Direct Dye Sublimation Print
102 SCREEN PRINT INDIA - July 2011
sublimation is simple,
clean and easier than
other processes.
But dye sublimation is not limited to decorating the fabrics only. Many products such as ceramic tile, mouse pads, mugs and plates can all be decorated using practically the same equipment, so
generating multiple lives for dye sublimation is quite easy.
Comparison with Screen Printings
One of the main advantages is that dye sublimation papers used for high quality sublimation transfers are designed to print a wide gamut of vibrant colors while enhancing the release of ink during the sublimation process, allowing for a permanent 'color pop' that does not fade over time. While the colors produced by screen printing are comparable to dye sublimation, screen printing usually requires large minimum order quantities and tooling costs. Alternatively, sublimation enables the fl exibility to produce one-offs digitally with the image permanence of screen printing at a fraction of the cost, allowing print providers and sign shops to produce
One of the main advantages is that dye sublimation papers used for high quality sublimation transfers are designed to print a wide gamut of vibrant colors while enhancing the release of ink during the sublimation process, allowing for a permanent 'color pop' that does not fade over time.
Technology
Comparison of Direct and Transfer Dye Sublimation PrintsDirect Dye Sublimation Transfer Dye Sublimation
Prints directly on the fabricsNeeds the medium, normally paper, for transferring
the print on the fabric
Cost of printing machine is more Cost of printing machine is less
Material cost is less Material cost is high
Labour cost is less Labour cost is more
Production rate is high Production rate is less
Cost of printing is less Cost of printing is more
Less wastage More wastag
Best print are limited to flat, smooth surfaced
fabricsExcellent on knitted fabrics
Quality of print is not that much superior as
compare to TransferQuality of print is superior as compare to Direct
Suitable for longer length fabric Suitable for panel printing
More application are there in home furnishing,
banner, backdropsWidely used in apparel sector
Polyester Poly/Cottons Canvas Rayon
Acrylic Satins Dacron Poplin
Faux Suede Nylon Nylon 66 Ripstop
Poly Felts Voile Baize Lycra
Fig 7 Comparison of Screen Print
and Direct Sublimation Print
104 SCREEN PRINT INDIA - July 2011
items as ordered rather than committing to a large inventory position. See Fig. 7.
Comparison with Digital Inkjet Printing
Dye-sublimation differs greatly from inkjet
in many ways; most signifi cantly in quality.
Dye-sub is known for its high quality and
continuous tone output. Continuous tone
means that all gradations of colour are used
when creating an image. For example, when
creating a grey scale, from black to white, a
continuous tone printer will show all shades
of grey in between the black and the white
by actually printing them. See. Fig. 8.
A half-toning device such as an ink-jet
printer will use a dithering technique of
placing dots close together in order to trick
the eye. In other words, ink jet printers use
a series of black dots placed close to white
dots in order to trick the eye into blending
the pixels when viewed. With magnifi cation
the difference can be seen where the dye-
sub output is clear and sharp, but dots can
be seen on ink-jet prints. Dye-sublimation
printing has an important advantage over
Inkjet printers - the ability to print a superior
range of colors. Dye-sublimation printers
are able to change
the temperature of
the thermal elements
in its head at 256
different degrees,
therefore producing
256 different shades
of each of the
colored panels. More
importantly, due to
its properties, the dye
is transparent and
colors can be laid on
top of each other,
combining to produce
16.8 million different
shades. The technology also features a fi nal
laminate coating which makes prints from a
dye-sublimation devices look as if they have
been developed from a photochemical lab.
Another advantage of dye sublimation is
that the prints are dried up and able to use
when they get out of the printer. Considering
that thermal head doesn’t have to sweep
backwards and forwards above the print
media, there can be fewer moving pieces
which could break down. Since the dye in
no way enters a liquid phase, the entire
printing cycle is extremely clean; one can
fi nd no liquid inks to clean up along with
no print heads for getting clogged. These
variables cause dye-sublimation usually a
more trustworthy technology over inkjet
printing. Dye-sublimation has another two
major advantages over Inkjet technology. UV
& Water Resistance.
However, dye-sublimation printers also have
some drawbacks over their inkjet rivals. Each
of the colored panels of the ribbons, and the
thermal head itself, match the size of the
media that is being printed on. This means
that dye-sublimation printers cannot match
the fl exibility of the inkjet printer's ability to
print on a wide range of media. In addition,
dye-sublimation printing media and ribbons
are sensitive to skin oils, which affect the
sublimation capacity, and must also be free of
dust particles which can lead to small colored
blobs appearing on the printed media. The
current standard is to include special fi lters to
reduce the likelihood of these incidents, but
keep in mind that a speck of dust can only
affect one print as it becomes attached to the
print during the whole process.
Pros and Cons of Sublimation Printing
Pros .....• Dye Sublimation has the highest print
quality for printing on fabric/textiles.
Technology
Fig 8 Comparison of Digital Print
and Sublimation Print
A half-toning device such as an ink-jet printer will use a dithering technique of placing dots close together in order to trick the eye. In other words, ink jet printers use a series of black dots placed close to white dots in order to trick the eye into blending the pixels when viewed.
106 SCREEN PRINT INDIA - July 2011
• Dye sublimation offers excellent
durability, image detail and color
vibrancy.
• The fi nished print has no "hand," which makes them feel second to none.
• The technology is well-suited for popular newer trends in urban fashion and performance/wicking fabric markets.
• Additionally, dye sublimation offers the potential for product diversity that can benefi t a company since all of their business will not be in one product type.
• Sublimation dyes are permanent as they have become part of the fabric, and thus give the excellent fastness properties.
• It is the most eco-friendly printing.
• Dye sub is great for full color designs on white or light colored garments.
• There is no crack or fading of colors in this type of printing.
• Dramatically Reduced Waste and Maintenance Costs.
• Excellent Coverage and Extended Ink
Yield.
• Trouble-Free Unattended Printing and
Maximum Uptime.
• Can print larger print sizes screen
printing.
• Photographic quality image capability
Cons .....
• The drawbacks of dye sublimation
include higher cost of dyes.
• It can be applied to a limited, more
expensive apparel choice.
• Nevertheless, niche markets that match
technology with need do exist and some
offer a handsome return.
• It can only be printed on white colour.
• Suitable for limited fi bers like dryfi t, silk,
polyster fabric.
• It cannot be printed on black or dark
colour fabric.
• Metallic colours are not possible.
Conclusion
Over the last decade, textile printing sector
has redefi ned itself as the contemporary
fashion statement of textile industry. World
over it is emerging as not only the most
'in demand' area, but also as driver of the
further growth of the textile industry. One
of the factors to catalyze this is the rapidly
transforming consumers. Emerging and
changing consumer needs have forced
companies to redefi ne their business
approach. It is the diversity of ideas that is
deciding the product lines.
Emerging expectation from design is highly
evolved and much diverse nature. Providing
product that attracts the buyer because of
Over the last decade, textile printing sector has redefi ned itself as the contemporary fashion statement of textile industry. World over it is emerging as not only the most 'in demand' area, but also as driver of the further growth of the textile industry. One of the factors to catalyze this is the rapidly transforming consumers.
Technology
108 SCREEN PRINT INDIA - July 2011
Technology
something other than the price is much
required. Many of the popular decorating
methods such as screen printing and
embroidery are time tested choices for
the apparel market. However, markets
inevitably change, fashion trends and
consumer tastes change rapidly as well.
What's "hot" today is old news tomorrow.
New techniques, materials and processes
are being implemented to realize the
consumer expectations and aspirations in
much sophisticated manner.
Sublimation print can be used mainly on
the polyester fi bre, in the past, nobody
wanted to wear the garments made
out of a polyester fi bre because they
were uncomfortable and lacked many
of the desirable qualities of cotton. But
today, a number of manufacturers have
come up with new processes that have
resulted in polyester garments that are
soft, breathable, and comfortable even
in warmer temperatures, and with the
increase in application of polyester fi bre in
the apparel segment sublimation will also
grow at the same rate.
Further, the increasing availability of new
and improved combinations of dyes, media, hardware and software are fuelling the usage of sublimation as a less expensive, long lasting, and customizable alternative to direct and screen printing methods. Breakthroughs in technology will also likely lead to sublimation playing a larger role in the sign industry, particularly in instances where it is preferable for signs and displays to be used multiple times.
With the new generation of wide-format digital printers, the creative possibilities for producing applications using dye sublimation are endless. Prior to these technological advancements, entering the dye sublimation market required a considerable investment of time and money, but now it is often favoured as a less expensive alternative to other printing methods.
Dye sublimation is a top contender for color vibrancy, durability and image detail. Newer urban fashion trends use dye sublimation and are generating a new wave in fashion apparel. Dye sublimation is rapidly gaining market share due to the increasing availability of new and improved combinations of dyes, media, hardware and software that have pushed the quality range to higher levels. In today’s market, it remains the preferred method over direct printing.
Vasant R. Kothari is Assistant Professor, Department of Fashion Technology, NIFT, Bangalore. Committee Member
of The Textile Association of India (TAI), Karnataka Unit. He can be contacted @ www.vasantkothari.com
Sublimation print can be used mainly on the polyester fi bre, in the past, nobody wanted to wear the garments made out of a polyester fi bre because they were uncomfortable and lacked many of the desirable qualities of cotton.