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The Foil that Came in from
the Cold Understanding cold
foiling as a straight forward
technique for brand enhancement
White paper
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Author: Will Oldham
Synopsis
“When it comes to cold foiling,
we avoid it because it’s
just…difficult” Said by a printer
with 15 years’ experience
Cold foiling is by no means
a new technology. Developed in
the 1990s for narrow web
printing, it was designed to
provide a cost-‐effective alternative
to hot stamping foil, specifically
for inline processes. When the
technology was first introduced it
was difficult, and at times
unpredictable, as each company
developed its own products with
little synergy across the component
parts.
It is the early beginnings of
the technique that has caused
much of its reputation.
However, cold foiling has now
matured into a proven printing
process. Machinery manufacturers and
the substrate, adhesive, ink and
foil suppliers have collaborated to
ensure all elements work together.
As the technology has advanced and
the results have become increasingly
reliable, rapid growth in cold
foil use has followed.
Cold foiling has moved on
significantly since the early days
of long web paths and cationic
links. It is now a legitimate
and proven process which provides
a cost-‐effective solution for
creating brand differentiation. However,
the industry perception is still
influenced by the output of the
early technology.
This whitepaper discusses the various
elements and the individual
requirements of each to demonstrate
that cold foiling is now a
straight forward technique. It
details each stage, consideration and
potential pitfalls of cold foiling,
and gives a broad understanding
of how to achieve the optimum
results.
“These days it’s one of the
simplest processes in print” Said
by the same printer with 15
years’ experience
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About API Group
API is a leading manufacturer and
distributor of foils, laminates and
holographic materials, which provide
exceptional brand enhancement for
consumer goods and printed media
worldwide. With roots in the
British paper industry, the company’s
reputation is founded on a
trading history going back over
a century. Operating from thirteen
locations across Europe, America and
Asia, API’s packaging solutions
enable companies across a wide-‐range
of industry sectors, including
premium drinks, confectionery, tobacco,
perfumery, personal care, cosmetics
and healthcare to empower their
brands on the shelf and in
the hand.
Will Oldham, Chief Commercial Officer
at API, has been in the
graphic industry for 30 years,
and has authored this whitepaper,
detailing his knowledge about cold
foiling and the opportunities they
can provide.
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Cold foil construction
The construction of foil for both
web-‐fed and sheet-‐fed is the
same and is made up of
five layers. Cross
Section of foil
Once applied and the carrier
removed, cold foil is two
microns thick. In comparison, a
hair’s breadth is between 40-‐120
microns.
There are now two forms of
cold foiling; web-‐fed and
sheet-‐fed. Both forms require the
following three-‐step process:
1. Print adhesive 2. Apply and
nip foil 3. Remove foil carrier
For both processes the same basic
principles apply: with the correct
combination of machinery and
component parts, it is a
straightforward and economical way of
adding eye-‐catching effects to
product packaging.
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An overview of cold foiling
benefits
Inline production
Perhaps the most cost and time
effective aspect of cold foiling
is its ability to be applied
inline, meaning that the printing
process does not need to be
offset, it is simply another
printing stage.
Shorter set-‐up times
The simplicity and low cost of
adapting most UV presses makes
this technique easily accessible to
printers who would not otherwise
invest in expensive hot foiling
equipment.
Easy registration
This reduces set up time and
wastage since foiling is not
affected by the thermal expansion
of dies. The adhesive is
printed like an ink and will
hold register like an ink, the
foil will then only stick to
where the adhesive has been
printed.
Lower die costs
Rather than using a brass hot
foil die, cold foiling uses a
printing plate, which can be up
to 98% cheaper. Using a plate
reduces cost and gives the
customer flexibility to add foil
without a premium price.
Design benefits
The chemistry involved in the
manufacture of a cold foil is
different from a hot stamping
foil, as it relies on a
peel-‐off mechanism, which is purely
physical and relies on the
attraction and tack of the
active components. This means that
it allows substrates that would
have previously been difficult and
even impossible to apply (such
as thermal stocks, plastic laminate
tubes and heat sensitive flexible
packaging) to benefit from decorative
foil.
A hot foil is designed to
have the release and adhesive
layers activated by heat and
pressure, so heat sensitive
substrates can melt and burst.
Cold foiling also presents a wide
range of creative opportunities as
it performs well on fine lines,
large area coverage, over printing,
half tones and multi-‐coloured
effects.
General limitations
The advances in cold foil
technology, whilst impressive, cannot
replace the finish achieved using
the traditional hot foil method,
especially where uncoated and
textured surfaces present particular
difficulties for cold foiling. Hot
foiling has an advantage on
fibrous, textured and absorbent
surfaces, thanks to the level
of pressure that can be applied
during the stamping process, serving
to even out and flatten
textured surfaces.
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Cold foiling is also unable to
provide the true mirror shine
that hot foiling produces. The
metallised layer in cold foil
is thinner, due to the need
to allow UV energy to pass
through the layers of the foil
and activate the UV curable
adhesives.
“The results that can be achieved
are amazing, from solid areas
to fine text”
Phil Baldwin, Mark Andy
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Web-‐fed cold foiling
Cold foiling on web-‐fed
processes is flexible and suits
a range of substrates. Being a
cold process, it is ideal for
heat sensitive materials, such as
films and shrink sleeves. It
works particularly well on the
‘no label’ look label that is
growing in popularity for products
like shampoos and beers.
Applications include:
• Filmic self-‐adhesive labels • Paper
self-‐adhesive labels • In-‐mold labels
• Shrink sleeve • Cartons
In the majority of cases, the
application of the adhesive is
by a flexo process. It can
be used in conjunction with the
full range of web-‐fed printing
processes, depending on the press
used. Typically, the presses will
be equipped with UV curing,
though there are examples of
solvent-‐based web-‐fed printing.
Typical ink printing processes:
• Flexo • Offset • Letterpress • Gravure
• Screen
Machinery for web-‐fed cold
foiling
The machinery requirements for cold
foiling are relatively simple, as
it only requires a unit to
roll on the foil and roll
off the corner. The adhesive
itself is applied in one of
the printing stations and should
be treated as any other print
process.
The new generation of wider web
presses is bridging the gap
between labelling and packaging. For
example, the Gallus IC5670, a
printing press for web-‐fed flexo
printing, can incorporate other
printing processes such as carton
production, which is traditionally a
sheet-‐fed process.
Most print manufacturers now supply
cold foil units, either as an
integrated part of a new press
or as an optional unit, meaning
that brand new systems are
ready to apply cold foiling and
old systems can be retrofitted.
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Machinery suppliers with cold foil
modules include:
• Edale • Gallus • Mark Andy • Nilpeter
• Gidue • Omet • MPS • AB Graphics
For a more detailed overview of
recommended suppliers please see
Appendix 1.
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Substrates for web-‐fed cold foil
The substrate is the critical
element when choosing the correct
foil. For cold foiling, the
rule is, the smoother the
substrate, the better the results.
Film, paper and board are the
three key materials suitable for
this technique.
The properties needed for the
processes include print receptivity,
a base stock within its shelf
life and in general, coated
papers are better.
All filmic substrates (PE, PP,
PET, PVC), are ideal for cold
foiling as they are non-‐porous
and prevent the absorption of
adhesive. It also allows clean
edges and low weight of
plastic.
The key factors for laydown
(appearance) include surface topography,
adhesive, weight and chemical
affinity. The key factors for
adhesion (appearance and performance)
include chemical compatibility, UV
curing, wetting and chemical/physical
bond strength.
Conventional coated papers and board
are suitable for cold foil
printing. Uncoated papers may be
successful if they are heavily
calendared, not too absorbent and
thoroughly tested.
It’s worth noting that on uncoated
surfaces, too much adhesive makes
the foil swim, but too little
adhesive and there is no foil
transfer.
Adhesives for web-‐fed cold foil
For web-‐fed cold foiling only UV
adhesives should be used.
When working with UV adhesives for
cold foil there are many
elements to consider, for instance,
the type of image area to
be foiled, as it could be
solid, text, or vignette. If
printing onto absorbent stocks, it
has to be able to support
the design.
During the specification process it
is also important to consider
the following:
• What is the base stock? • Do
you have the correct balance of
line count vs. depth for
optimum
release? • Is there fine text or
dot on the design? • Has the
anilox been deep cleaned? Is it
free from damage?
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API foils for web-‐fed cold
foiling
TO grade Specialist foil developed
with superior UV over-‐printing
capability
TA grade
A high speed over-‐printable foil
designed to be as versatile as
possible across machines and
substrates, while delivering the best
combination of fine detail and
broad area coverage
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Sheet-‐fed cold foil
Sheet-‐fed and web-‐fed printing is
significantly different. The key
applications for sheet-‐fed are web
glue labels, commercial print jobs
and cartons. The adhesive and
ink printing process are offset
and both conventional and UV
curing adhesives can be used.
Typically, the adhesive is applied
on the first unit and the
foil on the second unit is
followed by the ink print
units. However, there are machines
where the adhesive and foil are
applied further down the press.
For sheet-‐fed printing, there is
a range of systems either fully
integrated or suitable for retrofit.
Sheet-‐fed presses with cold foil
modules:
• Heidelberg (Foilstar) • Manrolands
(InlineFoiler) • Komen
Retrofit modules
• Foil Tone • Compact Foilers • Eagle
Systems/Graphic Art • Vinfoil
For a more detailed overview of
recommended sheet-‐fed machine
manufacturers please see Appendix 2.
Substrates for sheet-‐fed cold foiling
Considering the correct substrate, inks,
adhesives and foils is crucial
to ensure all elements work
well together. In all cases,
suppliers should advise what the
best possible solution is.
The most suitable substrates for
sheet-‐fed cold foiling are paper,
board and plastics, with an
emphasis on paper and board.
The smoother the substrate, the
better the results, which is
why paper and board are ideal
materials to work with. It’s
worth noting that matt plastics
should be avoided.
Adhesives for sheet-‐fed
Adhesives should have the same
print characteristics as ink, with
tackiness to enable the foil to
stick and transfer from the
carrier. It’s important to use
the minimum amount of glue
required, as too much glue
leads to ‘scumming’ and excess
foil being applied. However, too
little glue leads to an
incomplete foil transfer.
For sheet-‐fed applications UV curing
& conventional (oxidatively) drying
adhesives can be used.
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API recommends the following suppliers,
though there are a wide range
available:
Conventional (oxidatively) drying:
• Saphira (Heidelberg) • Printcom (Monrolands)
• Foiltone • Zeller + Gmelin • Huber
• Jänecke & Schneemann • Toyo Ink
Excessive adhesive could lead to
poor print definition or lead
to the carrier film breaking,
whilst insufficient adhesive application
could lead to poor removal of
the metallised layer from the
carrier film. It is crucial to
consider this during the
specification process.
The adhesives are coloured, facilitating
the control of even film
weights using a densi-‐toner. For
overprinting, we recommend the UVALUX
U7/U73 or UVAFLEX Y7 series.
Containers of the UV adhesives
should be closed immediately after
use and should always be stored
in a cool, dark place. The
optimum storage temperature is about
20°C, to ensure it is protected
from high temperatures and
particularly frost.
In addition, ensure it is stirred
well before using and always
clean the printing unit with
washing agents. Be aware that
the addition of any additive
may change the overall characteristic
of the adhesive.
Cold foils for sheet-‐fed The key
properties for cold foil for
sheet-‐fed are exactly the same
as for web-‐fed. They have a
very free release, good bond to
adhesive and good receptivity to
inks.
API foils for sheet-‐fed cold
foiling
TU Grade The TU grade is
specifically designed for inline cold
foiling with UV curing adhesive
and inks. It is also suitable
for conventional (oxidatively) drying
adhesives and inks.
Inks It is important to use
inks formulated for non-‐absorbent
surfaces, such as films and
foils. High-‐tack ink, for use
on plastics and other materials,
may need tack to be reduced
to minimise foil transfer onto
ink printing blankets.
Contact your chosen ink supplier
for more information.
For an overview of recommended ink
suppliers please see Appendix 3.
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Appendices
Appendix 1
API recommends the following web-‐fed
machines, though others are
available. Gallus Gallus have
a range of machinery from the
flexible ECS 340/330, which can
expand as your requirements grow;
to its ICS 670, a wide
web machine for folding carton
conversions.
Nilpeter Nilpeter cater for a
broad range of printing options
and is easy to control. The
multiple process press incorporates
easy load sleeve technology and
has an instant set up register,
ensuring low waste and reduced
set up times.
Edale FL-‐3
“The Edale FL-‐3 combined with API
Foil’s cold gold foil received
positive feedback from the trade,
in which they reported that
they have never seen a better
lay down of foil.” Douglas
Storrie, Edale
Appendix 2
API recommends the following sheet-‐fed
machines though others are available.
Heidelberg The Heidelberg Foilstar
applies foil on 76mm cores and
includes single width rolls and
multiple slit rolls. It is able
to apply large-‐scale metallic
finishes and provides significant
cost savings because of its
multi-‐reel operation and indexing.
It also does not require
metallised paper or board.
Manroland InlineFoiler The Manroland
InlineFoiler applies foil on 152mm
cores for single, wide rolls
and on 76mm cores for multiple
slit rolls.
Foiltone Foiltone is a UK supplier
with deep roots in the print
industry. The company developed and
built the first retrofit cold
foil systems in 2006 and
provides units for all press
makers and sizes. The differential
shafts allow customers to run
several narrow rolls or one
full size roll.
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Appendix 3
Recommended ink suppliers:
• Flint • Huber • Jänecke &
Schneemann • Paragon Inks • Printcom
(Manroland) • Saphira (Heidelberg) • SICPA
• Siegwaerk • Sun • Zeller + Gmelin
Appendix 4
Coatings API always recommends using
a varnish or lacquer to protect
foil and inks from rubbing.
Doing so increases resistant
properties and provides a high
quality finish.
For more information, contact your
chosen coating supplier.
Appendix 5
What the printers say:
Windles Group
• Amazing sheet coverage • Ultra fine
detail, including reversed out foil
areas • Flexible colour selection
through the use of CMYK palette
of inks on foil • Multiple
colour choice over the sheet.
As many colours as you want
on one
pass • Unique metallic imagery •
Excellent registration • No deformation of
the material • No need for
expensive foil dies • High-‐speed
foiling
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“The main factor for ensuring a
job runs smoothly is client
support. It is important to
design with the process in
mind. There can be easy
mistakes made if mis-‐handled, both
at the design stage and
production. But executed well,
nothing can beat it.” Ian
Kear-‐Bertie, Windles Group
MPS
• Cold foil introduced as product
sustainable alternative to other
methods • Additional option to
‘premium-‐ise’ packaging • Allows finer
detail and increases the finished
and effects options • Extends
capabilities with in-‐line processes
• Does not replace hot stamping
foil
Berkshire Labels
• Low cost origination • The flexibility
of producing the origination
in-‐house • Full rotary production
speeds • Ability to foil across
multiple presses that we currently
have • Ability to produce tints,
screen, vignettes etc in foil
“Cold foil is not the answer
to everything and there are
some substrate incompatibilities but,
coupled with our hot foil
capabilities, it gives us a
very economical and flexible option.”
Paul Roscoe, MD, Berkshire Label
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The Foil that Came in from
the Cold
API Group Second Avenue Poynton
Industrial Estate Stockport SK12 1ND
UK +44 (0)1625 650500
www.apigroup.com [email protected]
